Sounds like there may be a driver loading when not in safe mode that's causing this issue.
Please run the application msinfo32 on your machine and follow the steps in the app to save the output to a file.
Then post that file in a public folder on http://skydrive.live.com and post the link here. I'd like to see what other apps are installed.
Want to know if your current hardware & software will work with Windows 7? Check out these links: **Windows 7 Upgrade Advisor ** **Windows 7 Compatibility Center**