Why is my computer freezing during Scandisk?

It reaches step 4/5 and gets frozen at 0%, and has been acting very strange today. I havent done anything with it that I normally wouldnt, and its been very slow and not running properly in the past few hours. And now that I try Scandisk, it gets stuck, unable to get past 0% on step 4 out of 5. Can anyone help me? I can't get on my computer if it doesn't finish. These are the kind of thigns Im seeing, "Deleting an index entry, Fixing mirror copy of the such-and-such, Security descriptor verification, CHKDSK is verifying usn journal, usn journal verification complete, CHKDSK is verifying file data, then 0 percent completed", and that's where it's stuck. Also, the computer is VERY hot, it's never been this hot. What should I do about this? It is a Windows XP laptop. I just recently had to reinstall my OS, and it's been running just fine until today.