I always install SP2 with win2k 1st before I do anything else. I think it helps to build your system off of a firm platform. SP2 tends to fix errors you didn't even know you had. Then when you install the drivers, they're being put onto somthing stable and good. Otherwise it's putting drivers onto an unstable system and then upgrading the system. Start as fresh as possible. It's goes a long the same lines as formting ideas.
I relate it to painting, when you paint you want to scrape off the old paint, and only then do you apply the new paint. Formating is scraping off the old pain, because if you just upgrade, your paint is going to peel (all kinds of errors and problems you didn't know u could have.) The SP2 is like the 2nd coat of paint and drivers are like pictures or posters, when you install the drivers 1st it's like putting up a picture and then painting the 2nd coat around it. Underneath the picture, there's only one coat, not the 2nd. You want to apply the 2nd coat to the whole wall 1st, then put up your pictures. Then the room / comp will look / run like a dream.