I'm not using Catalyst just the ATI driver that came with the machine.
ATI's drivers are called "Catalyst", so if you don't have catalyst, then you don't have ATI's drivers. There is a "driver only" version, and a "suite" version, but both are "Catalyst".
The version that "came with the board" is guaranteed to be quite outdated, and likely full of issues for your card. The first rule with new hardware -- and especially quickly changing hardware like graphics cards -- is to put away the driver disc and download updated drivers from the manufacturer.
Never use the disc unless you've checked and confirmed that it's the best version to use. (Oh, and if you mean the driver that comes with Windows and installs automatically, then you REALLY need to get the proper driver. That driver was designed for the second generation Radeon 7x00 series GPUs.)
Anyhow... If you're getting a blue screen related to the video card driver, you really ought to download the newest one. ATI releases a new version of Catalyst once per month. Go to
http://www.ati.com/ and download the current driver (currently 6.11 for your card, 6.12 isn't listed as supported for some reason). Since you have an AIW card, you'll also want to grab at least the DAO/MDAC and Encoder Package components of the Multimedia Center package. If you don't use ATI's MMC program, you don't need the rest of it, though it won't really hurt too much (except for file type associations). Then, make sure to uninstall whatever you have (unless it's just the default XP driver), reboot, and install the Catalyst driver. You can decide if you want the full Catalyst Control Panel suite, or just the driver. I'd get the whole suite unless you're going to use a third party tool like ATI Tool to configure the card. You also won't get the WDM drivers without the whole suite, so you won't be able to use the AIW functions of your card.