check these things

is UAC disabled?
do you have enuf space?
is your hardware up to snuff?

UAC = user account control, goto the contol panel and select it and disable it and restart vista

which version of vista are you running? i have ultimate and it runs max fine. vista is still in early stages, i know 3ds max 8 didnt work for me untill i got windows xp SP 2, but that might just be me. there are alot of programs that dont work with vista yet, and most of the video card drivers are either still in beta or have a heck of alot of updates coming.

i havent been updateing mines because all i use vista for is h2v 3dsmax and h2ek, thats it. xp handles internet and email

Dont beleve that bull****. UAC does NOTHING. As long as your not downloading viruses(You should have a good antivirus) and checking for spyware(good antispyware) then you should be fine. I have always had UAC disabled and Im perfectly fine, All i do on it is model, play h2v, play bf2142 demo. Thats it and I have no problems.

Well if you wanna download illegaly, and watch tons of porn. Then yes dont disable it(but then again you have other problems) But for the everyday person I dont see why not. And for the hardcore gamer it is a MUST! None of your games will run or they wont run 100%

I can give you a list
1. It stops main processes from being launched on most apps
2. Makes vista less backwards compatable
3. It limits the access to memory needed by a app
4. Its annoying as **** when it comes to running ANYTHING!
5. ITS JUST PLAIN ANNOYING!
6. Disable it if you can, dont go against what your boss says(if its a job pc)
7. If you arent getting on virus infested sites then you would have no problem
8. Run spyware/adware/virus checked and no problem

:/ Dang on Dennis...Now I cant reply...