Vista - Installshield wizard wont install my games, no error though

Hello , i recently bought a new computer from dell, and have installed a few
games ot play on it, but frustratingly some install perfectly and some dont.

the problem seems to be with installshield wizard as the installshield loads
up fine but when it tries to install the actual game it just stops installing
at the start of the installation.

here is what happens>>
http://img88.imageshack.us/img88/4339/vistaerrormn5.jpg

thing is my system continues to run perfectly it doesnt slow down and i get
no error messages from it, it just stays like its installing forever. i have
tried to run it under a different compatability (xp sp2) and the same error.

I see there is a hotfix on microsoft's site , however that is for an games
that are installing and not using installshield 12 right? , enemy territory
quake wars DOES have installshield 12 and the problem persists.

Try this:

Delete folder C:\Windows\SysWOW64\InstallShield and everything in it.

Run...cmd...sfc /scannow

It will restore the folder and might help you.