Again, you will need to install Windows 7 drivers for your components, as Brink is right when he says you will need to "reinstall" drivers.
In short simply copying drivers from one OS to a completely different one won't work!
When Tews says Windows will have most of the drivers, he's talking generic, and these WILL NOT include the sound, video, and other drivers needed for full functionality of the components. Again, you will have to find the specific drivers needed for these components to work under Windows 7
Sorry.