I had the same problem.. if you pay attention, you'll notice the blue screen of death for a second before it reboots..
Press F8, select SAFE MODE, and install the drivers from the CD provided.
Lastly, install the ATI control panel.. and tell me if it shows up for you.. cuz for me it never shows up on the task bar, and it seemed to have killed the task bar, since nothing shows up on it! (and I'm an IT Professional, and know the inside out of XP, and still can't find the solution online for it!)