Something is wrong with my PS3 (and its not YLOD)

There’s a serious problem with my PS3. I boot it up, and everything goes smoothly, I can log into my master account, but when I get to the XMB, nothing will load. The game list won’t, the PSN listing won’t, everything except for the section that gives you Network Settings, System Update, Theme, and so on. But when you select any of those options, the PS3 freezes. I’ve tried restarting the system, and the problem persists. Can any one solve this problem, or at least, if anyone has this problem too?