Hello and Welcome to Windows7forums..
Ok so first of all you didn't back up your system.. (which was your first mistake).. second you listened to a friend (which was your second mistake) and third you didn't do a clean install..
So as previously said, your going to have to do a clean install and since you don't have your original OS disk you'll have to reinstall Windows 7.. Now, your bitching about 7 why exactly? If you did an upgrade then there's no one to blame but yourself..

You can't expect things to work 100% after doing an Upgrade install.. I'm not saying it's impossible but it's very rare..
If you did happen to not erase the recovery partition then you can always restore that and use Vista again.. I still don't see why you want Vista over Windows 7 though? If you did an Upgrade instead of a clean install then you really haven't even given Windows 7 a chance..
Windows 7 is by far much better then Windows Vista and XP for that matter..