repeated restarts+no paging file+corrupt and unreadable file C:\$MFT

I've been having multiple problems with my XPS 400 with Windows XP media center edition 2005. I keep getting a little popup that says "The file or directory C:\$MFT is corrupt and unreadable. Please run the Chkdsk utility." I've done this multiple times, even using /F. A post on the forums said to do a sort of system repair using the windowsXP install CD, but that ended in a bluescreen stop error which dell support had me fix by running a repair install with /R. I still get the error. I also get an error when windows starts up saying there is no paging file or the paging file is too small, but when i change it in control panel to around 2000-4000 and restart, I still get the message. Also, the computer seems to spontaneously freeze up and restart (maybe connected with paging file problem?). Compounded on all these issues is a problem i have with installing any devices/drivers/virusprotection i've tried. I get errors like Error 1926 could not set file security for file C:\Config.Msi\. and Error: 1392. Verify that you have sufficient priveleges to modify the security permissions for this file. Mine is the only account on the computer and it has administrator status, so i'm not sure why i get these security errors. My Mcaffee that came stock stopped working after an update a while ago, so i totally uninstalled it, but couldnt reinstall it because of these errors. Does anyone please have a clue where to start with this mess short of a total reinstall?