Vista 64 and Nothing Works, please help

Hi, I'd been using a dell XP sp3 desktop and all of my software in question worked fine. I just upgraded to a dell vista 64 desktop and now none of my video copying/burning software will work. I copy DVD's with DVDFab, DVD Decrypter and DVD Shrink and create DVD's from Tivo recordings using Roxio Creator 2009. Now everytime I try to use any of them after a clean install and updating all the software, error messages come up saying the program(s) stopped working. I have many times the RAM and processor speed as in my old PC and have no idea why this is happening but I usually copy/create many DVD's a week and now can do nothing. It seems like with anything I do that begins using a lot of processor/memory for video data processing, vista is shutting it down for no reason. If anybody has any info on this please help because it's making me insane.