First and foremost. DO NOT MULTIPOST!!!
Posting with in 5 minutes of yoruself is a good way to get banned for spamming. Not every person is on this site looking at your post. If you are in such a rush call Steam support. Till then give 24 hours before bumping your own topic. Common courtesy.
This is your 1 and ONLY warning on that matter.
If the drivers are not Vista compatible there is NOTHING you can do. Get driver that are for your OS or dont use the options for the mouse.