Okay, I've taken the computer out and popped it open. There are two large bays and four small bays: one large bay is taken up by the CD-RW/DVD-ROM drive, and three small bays are taken up by the hard drive, various sockets (like for headphones and USB), and a bunch of memory card slots. The last I find kind of irritating, because while it's something I might've liked to have had just for "extra geegaws" bonus geek points, it's not something I'd ever actually use (I have no digital camera and, with my swanky SLR, no real desire for one) and it takes up a valuable spot where I could put a hard drive. I could take it out, but the case is designed so there's a hole for it (fucking made-for-a-single-configuration cases) and it doesn't come with a flat replacement faceplate. The other option is to buy some sort of adapter for fitting a hard drive in a large drive bay—but that would put that drive right next to the CD/DVD, which probably runs very hot.
This is sort of pissing me off*, since I'd been looking at cases with several internal drive bays, which had the sockets next to them so they didn't take up any bay space.
I really shouldn't be this annoyed by a gift like this.
EDIT: *Just to clarify, I'm not pissed at my parents. I'm pissed at Compaq for not using more configurable cases.