All in all this system looks great. Let me mention something about this card that everyone is concerned with. Aureal made some GREAT sound cards, and while the SBLive is a good card, the reason people recommend it are for compatibility and drivers! Personally, I'd rather own something that does certain things VERY well, like the Aureal card! They have some great effects you can do with that card. Stick with the one you've chosen, how often do you update soundcard drivers anyhow? hehe I mean seriously... I update drivers in two situations, when I first install the OS and when I have a problem with a device, which is almost never.
The thing I WOULD upgrade is your motherboard. The MSI K7T Pro 2a board seems to be the favorite among TBird owners, definitely go with this board.
Second thing, make sure you buy decent RAM, it's all very cheap right now, but don't buy the cheapest stuff available, you can ruin a perfectly good system with bad ram, get cas2 brand name ram, such as Mushkin, Crucial, Micron, Corsair, Infineon, or Kingston, not the value ram though.
Third, if you plan to play any games with this system (and I can't see why you would not with an 800 mhz machine) then upgrade to an NVidia GeForce2 MX card, at the very least. This will last you probably 1 1/2 years, but anything less will be obsolete before 2001 is overwith, if you plan to watch any 3d graphics.
Lastly, make sure you get a brand name Cd-ROM! Unless you want jets taking off from your PC's case, then get a Plextor 40x or something similar, I know that particular drive is FAST and quiet. =) Not to mention just about everyone who owns it, swears by it (and no I don't own one, so I'm unbiased, just seen it in action).
You choice of processor and hard drive are definitely on track. Stick with what you've chosen.
divinemartyr