쩝 바뻐성 걍 제가 썼던거 그대로 올립니다. 그래서
중간에 쓸데 없는 코드도 있을수도 모자란 코드도 있을듯...^^;;
제가 기본적이 상수랑 형은 같이 적어놓았습니다.
쩝....참고로 XP pro와 home 에디션이 정확히 구분이 되는지 모르겠습니다.
홈에서 테스트 해봤는데 프로로 나오더군여 근데 바뽀성 안고쳤습니다.

msdn욜라 찾아서 데파이로 바꾼겁니다...힘들었는뎅......배아포....

//선언부--------
type
  LPOSVERSIONINFOEX = ^TOSVERSIONINFOEX;
  POSVERSIONINFOEX  = ^TOSVERSIONINFOEX;
  _OSVERSIONINFOEX  = record
  dwOSVersionInfoSize : DWORD;
  dwMajorVersion : DWORD;
  dwMinorVersion : DWORD;
  dwBuildNumber :DWORD;
  dwPlatformId : DWORD;
  szCSDVersion :array [0..127] of char;
  wServicePackMajor : WORD;
  wServicePackMinor:WORD;
  wSuiteMask:WORD;
  wProductType : BYTE;
  wReserved : BYTE;
end;
TOSVERSIONINFOEX = _OSVERSIONINFOEX;

//
{ WINNT.H =====================================================================}
//

const VER_SERVER_NT                       = $80000000  ;
const VER_WORKSTATION_NT                  = $40000000  ;
const VER_SUITE_SMALLBUSINESS             = $00000001  ;
const VER_SUITE_ENTERPRISE                = $00000002  ;
const VER_SUITE_BACKOFFICE                = $00000004  ;
const VER_SUITE_COMMUNICATIONS            = $00000008  ;
const VER_SUITE_TERMINAL                  = $00000010  ;
const VER_SUITE_SMALLBUSINESS_RESTRICTED  = $00000020  ;
const VER_SUITE_EMBEDDEDNT                = $00000040  ;
const VER_SUITE_DATACENTER                = $00000080  ;
const VER_SUITE_SINGLEUSERTS              = $00000100  ;
const VER_SUITE_PERSONAL                  = $00000200  ;
const VER_SUITE_BLADE                     = $00000400  ;

//
// RtlVerifyVersionInfo() type mask bits
//

const VER_MINORVERSION                = $0000001  ;
const VER_MAJORVERSION                = $0000002  ;
const VER_BUILDNUMBER                 = $0000004  ;
const VER_PLATFORMID                  = $0000008  ;
const VER_SERVICEPACKMINOR            = $0000010  ;
const VER_SERVICEPACKMAJOR            = $0000020  ;
const VER_SUITENAME                   = $0000040  ;
const VER_PRODUCT_TYPE                = $0000080  ;

//
// RtlVerifyVersionInfo() os product type values
//

const VER_NT_WORKSTATION              = $0000001  ;
const VER_NT_DOMAIN_CONTROLLER        = $0000002  ;
const VER_NT_SERVER                   = $0000003  ;

//
{end WINNT.H ==================================================================}
//


const WIN32_NAME             = 'Microsoft Win32s  '             ;
const WIN95_NAME             = 'Windows 95 '                    ;
const WIN95_OSR2             = 'OSR2 '                          ;
const WIN98_NAME             = 'Windows 98 '                    ;
const WIN98_SE               = 'SE '                            ;
const WINME_NAME             = 'Windows ME '                    ;
const WINNT_HOME             = 'HomeEdition '                   ;
const WINNT_PER              = 'Personal '                      ;
const WINNT_PRO              = 'Professional '                  ;
const WINNT_SERVER           = 'Server '                        ;
const WINNT_ADSVR            = 'Advanced Server '               ;
const WINNT_DATSVR           = 'DataCenter Server '             ;
const WINNT_ENTSVR           = 'Enterprise Server '             ;
const WINNT_NAME             = 'Windows NT '                    ;
const WINNT_2000             = 'Windows 2000 '                  ;
const WINNT_XP               = 'Windows XP '                    ;
const WINNT_NET              = 'Windows .NET '                  ;
//선언부--------끝


//내가 사용한 함수
procedure DisplaySystemVersion();
var
  osvi : TOSVERSIONINFOEX;
  bOsVersionInfoEx :Boolean;
  hKeys : HKEY;
  szProductType : array [1..80] of Char;
  dwBufLen : DWORD;
  szCSDVersion : string;
begin

   // TOSVERSIONINFOEX 형을 GetVersionEx 함수로 호출한다.
   // 만약 실패하면 TOSVERSIONINFO 형식으로 호출한다
   ZeroMemory(@osvi, sizeof(TOSVERSIONINFOEX));
   osvi.dwOSVersionInfoSize := sizeof(TOSVERSIONINFOEX);

   bOsVersionInfoEx := GetVersionEx(osvi);
   if not (bOsVersionInfoEx)  then
   begin
      osvi.dwOSVersionInfoSize := sizeof (TOSVERSIONINFO);

      if not ( GetVersionEx (osvi) ) then
      begin
        osFullName := MRSUnknown;
        Exit;
      end;
   end;

   case osvi.dwPlatformId of
     VER_PLATFORM_WIN32_NT:
     begin
         if  ( osvi.dwMajorVersion <= 3 ) then
         begin
          osFullName:= WINNT_NAME;
         end;

         if  ( osvi.dwMajorVersion <= 4 ) then
          osFullName:=WINNT_NAME;

         if ( osvi.dwMajorVersion = 5) and (osvi.dwMinorVersion = 0 ) then
         begin
          osFullName:=WINNT_2000;
          ovdType := ovdWin2000;
         end;

         if ( osvi.dwMajorVersion = 5) and (osvi.dwMinorVersion = 1 ) then
         begin
           osFullName:= WINNT_XP ;
           ovdType := ovdWinXP;
         end;


         if bOsVersionInfoEx then
         begin
            if  osvi.wProductType = VER_NT_WORKSTATION  then
            begin
               if ( osvi.wSuiteMask = VER_SUITE_PERSONAL ) then
               begin
                  if ( osvi.dwMajorVersion = 5) and (osvi.dwMinorVersion = 0 ) then
                  osFullName := osFullName + WINNT_PER;
                  if ( osvi.dwMajorVersion = 5) and (osvi.dwMinorVersion = 1 ) then
                  osFullName := osFullName + WINNT_HOME ;
               end
               else
                  osFullName := osFullName + WINNT_PRO;
            end
//          end;
            else if  osvi.wProductType = VER_NT_SERVER  then
            begin
               if  osvi.wSuiteMask = VER_SUITE_DATACENTER  then
                  osFullName := osFullName + WINNT_DATSVR
               else if  osvi.wSuiteMask = VER_SUITE_ENTERPRISE  then
               begin
                  if ( osvi.dwMajorVersion = 5) and (osvi.dwMinorVersion = 0 ) then
                  osFullName := osFullName + WINNT_ADSVR;
                  if ( osvi.dwMajorVersion = 5) and (osvi.dwMinorVersion = 1 ) then
                  osFullName := WINNT_NET + WINNT_ENTSVR ;
               end
               else
               begin
                  if ( osvi.dwMajorVersion = 5) and (osvi.dwMinorVersion = 0 ) then
                  osFullName := osFullName + WINNT_SERVER;
                  if ( osvi.dwMajorVersion = 5) and (osvi.dwMinorVersion = 1 ) then
                  osFullName := WINNT_NET + WINNT_ENTSVR ;
               end;
            end;
         end
         else
         begin
            RegOpenKeyEx( HKEY_LOCAL_MACHINE,PChar('SYSTEM\CurrentControlSet\Control\ProductOptions'),
                          0, KEY_QUERY_VALUE, hKeys );
            RegQueryValueEx( hKeys, 'ProductType', nil, nil,  PBYTE(@szProductType), @dwBufLen);
            RegCloseKey( hKeys );
            if ( lstrcmpi( 'WINNT', @szProductType) = 0 ) then
                  osFullName := osFullName + 'Workstation ';
            if ( lstrcmpi( 'SERVERNT', @szProductType) = 0 ) then
                  osFullName := osFullName + 'Server ';

            if ( osvi.dwMajorVersion = 3) and (osvi.dwMinorVersion = 51 ) then
            begin
             osFullName := osFullName + '3.51 ';
             ovdType := ovdWinNT351;
            end;
            if ( osvi.dwMajorVersion = 4) and (osvi.dwMinorVersion = 0 ) then
            begin
              osFullName := osFullName + '4.0 ';
              ovdType := ovdWinNT40;
            end;
         end;

         osFullBuild := format('%d.%d.%d',[osvi.dwMajorVersion,osvi.dwMinorVersion,osvi.dwBuildNumber and $FFFF ]);
         osCSDVersion:=osvi.szCSDVersion;

      end;// end case VER_PLATFORM_WIN32_NT
      VER_PLATFORM_WIN32_WINDOWS:
      begin
         if (osvi.dwMajorVersion = 4) and (osvi.dwMinorVersion = 0) then
         begin
           osFullName := WIN95_NAME;
           ovdType := ovdWin95;

           if  osvi.szCSDVersion = 'C'  then
              osFullName :=osFullName+ WIN95_OSR2 ;
         end;

         if (osvi.dwMajorVersion = 4) and (osvi.dwMinorVersion = 10) then
         begin
           osFullName := WIN98_NAME ;
           ovdType := ovdWin98;
           if  trim(osvi.szCSDVersion) = 'A'  then
            osFullName :=osFullName+ WIN98_SE ;
         end;

         if (osvi.dwMajorVersion = 4) and (osvi.dwMinorVersion = 90) then
         begin
            osFullName :=WINME_NAME;
           ovdType := ovdWinME;
         end;
         osCSDVersion:=osvi.szCSDVersion;
         osFullBuild := format('%d.%d %d %s',[osvi.dwMajorVersion,osvi.dwMinorVersion,osvi.dwBuildNumber and $FFFF,osCSDVersion ]);
      end; //end case VER_PLATFORM_WIN32_WINDOWS
      VER_PLATFORM_WIN32s:
      begin
         osFullName :=WIN32_NAME;
         osCSDVersion:=osvi.szCSDVersion;
         osFullBuild := format('%d.%d %d %s',[osvi.dwMajorVersion,osvi.dwMinorVersion,osvi.dwBuildNumber and $FFFF,osCSDVersion ]);
      end;
   end;//end all case
end;