HELP!!!

[groovypancakes]

YAY! I found a place to get help! lol Well basically I got a new computer it's vista. I loaded sims2(and all my expansion packs - I don't think any of them are vista compatible) onto it and it was fine, then I loaded windows2007 (the newest office version) and it suddenly stopped working properly. It would basically just freeze randomly in the game. I can move my mouse sometime but "esc" doesn't work although "alt" + "tab" gets me out of the game but when I try bring it back again it's black with the sims sandtime thingey or the sims mouse design. Ok so I figured out that it was because they weren't vista and so I got a new base sims2 (the one with nightlife) that's compatible with vista and so I loaded it (without expansion packs) but it still freezes(same freezing as before) especially on CAS or when I just make a family and they are on their way to the neighbourhood...they never get there...it always freezes. I've checked my graphics and sound card and I'm perfectly compatible so I don't know what the hell is wrong with it! Please somebody help! Oh and I've tried to follow all the offical help stuff on freezing. I haven't even tried sims1 on it but should I and see if this works? I mean at least I'd have A sims to play! But I really don't want to mess up my baby computer! PLEASE SOMEBODY HELP!!! I haven't been able to play sims for absolutely ages! It's lkilling me! I keep trying but it just freezes!

Oh yeah my computer specs are: 160GB hard drive, 2GB RAM but as like a dual core and I know all the graphics and sound is compaitable because I got my computer to check it. I have Vista and then Windows Office 2007. I know I have enough space because I've checked this too. Seriously I NEED HELLLPPPPPPP! I'll go insane otherwise! lol well more insane...