Here's a more updated version of the bat file... covers all OSs...

 Code:
@echo off

ver | find "95" > nul
if %ERRORLEVEL% == 0 goto oldkix

ver | find "98" > nul
if %ERRORLEVEL% == 0 goto oldkix

ver | find "NT" > nul
if %ERRORLEVEL% == 0 goto oldkix

ver | find "2000" > nul
if %ERRORLEVEL% == 0 goto oldkix

for /f "tokens=2*" %%i in ('reg query "HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion" /v ProductName') do set OS=%%j

echo %OS% | find "XP" > nul
if %ERRORLEVEL% == 0 goto currentkix

echo %OS% | find "2003" > nul
if %ERRORLEVEL% == 0 goto currentkix

echo %OS% | find "Vista" > nul
if %ERRORLEVEL% == 0 goto currentkix

echo %OS% | find "2008" > nul
if %ERRORLEVEL% == 0 goto currentkix

echo %OS% | find "Windows 7" > nul
if %ERRORLEVEL% == 0 goto currentkix

echo Unknown OS
pause
goto exit

:currentkix
kix32.exe scriptname
goto exit

:oldkix
kix32_453.exe scriptname


:exit