Did you build your own system? If not, here is how to add another hard drive:
1. Mount the hard drive in a hard drive cage or wherever your case holds the hard drives.
2. Connect the IDE cable to the hard drive.
3. Connect the power plug from the power supply to the hard drive.
4. Turn on the computer.
5. Go into the BIOS.
6. Go to "Detect IDE devices" or something similar and you should see a new drive come up when it is done detecting it.
7. "Save Changes and Exit" from the BIOS.
8. Let windows boot up and it should detect the drive automatically.
Now, about copying the stuff- it will most likely be more time consuming than a fresh install. Plus, with a fresh install you can leave off those unimportant, resource-hogging programs that you've meant to uninstall but never did.

Just make sure you have all of the drivers and programs that you need on CDs (if you don't have the drivers- find them and use your burner.

).
The easiest way to remove your drivers would be Start>Control Panel>System>Device Manager>Display Adapters>Remove.
By the way, you will love that Radeon- my friend has an All-in-Wonder Radeon on a 1GHz Tbird+KT7 system (which I built

) and it rocks!