|Try taking the CDROM out of the boot order.|
Did CHKDSK return any errors.
Consider downloading the hard drive diagnostic utility from the hard drive manufacturers website and test the hard drive to make sure it's not failing.
Yes, you can do a fresh install without deleting the data. You'll need either a boot CD that can read the hard drive (like BartPE, Knoppix, other other), then rename the C:\Windows folder to something like C:\Old_Win and the C:\Program Files folder to something like C:\Old_Programs. The run the installation process WITHOUT FORMATTING the hard drive, and without the "Repair" option if it detects the old system folder.
Once the system is up, even if you create a user account with the same username and password you used before, a new profile folder will be created. But you can find the old profile folder under C:\Documents and Settings where your old \My Documents, \Favorites, \Desktop and other data will be.
Assume that I already did an Internet search.