I've moved your question to a seperate thread to stay on topic.
I have not yet tried win7, but in Vista you can set a game shortcut/exe to compatibility mode; XP SP2. Check if the option is available.
Also, have you installed DirectX 9? In Vista DirectX 9 is not available by default. You have to download it separately from Microsoft.
It would also help if you post the error and/or some screenshots of the error you get.
i have used Windows 7 quiet extensively on one of my test PC's Rfactor works fine but i however found a few other issues that made uninstall it.about 3 times iv tried and been happy for a while until something creeps in.I infact have tried differant Windows 7 and do remember one of them not wanting to start rfactor.