Can't run most 32 bit applications in Vista 64

This is the weirdest, possibly most frustrating, problem I've ever had >.>
Sometimes, all applications run & run well (interestingly, when I'm at my apartment though I know location has nothing to really do with it). Other times, I can barely run any applications at all. The ones I can run are: Comodo Internet Security, IE64, Ventrilo, and the command prompt. I can do things like go into the control panel, change my display settings, run Windows Update, etc. But I can't run: Firefox, Chrome, IE32, WoW, Avast, pretty much any installer, AIM and Winamp. This is a pretty fresh install so that's pretty much the summation of the programs I have installed / use. It's rather frustrating and I've tried reinstalling Vista which works until I reboot the computer. It just baffles me. I've searched around Google without much of any luck at all.
I've watched the task manager and sometimes the applications will show up in there briefly but then they quit very quickly. So I'm really unsure as to where to go from here.. if anyone has any suggestions I'd love to hear them :]

Thanks

Are you running with User Access Control disabled? If not, give it a shot? Sounds like almost the point of where Windows would intercept for ACL's.

I do have UAC enabled. I'm back at my apartment and everything magically works again.
/baffled

I'll try disabling it if it stops working again when I'm at my moms. Also might be worth noting that the programs will run in safe mode as well.

Could have something to do with it. There are, of course, inherent risks to running with UAC disabled, but checking it out could def. point you in a diagnostic direction. Will require a reboot following the change. I'll save you the search: