Go to START-->RUN and type in: sfc /scannow <--NOTE the space between sfc and /scannow.
You will need your XP cd to do this. This will check and make sure all your operating system files are in their original condition and replace any that aren't. Once the blue bar goes away, reboot your computer and see if the problem still exists.
Even if it doesn't still exist, I suggest you run DISK DEFRAGMENTER, but going to START-->RUN-->ACCESSORIES-->SYSTEM TOOLS and clicking on DISK DEFRAGMENTER.
DON'T RUN DISK DEFRAGMENTER WHILE DOING THE sfc /scannow. DON'T DO ANYTHING WHILE IT'S RUNNING. Best to do it while you are sleeping because it can take awhile depending on the size of your hard drive.
Post back how things are going after doing these two things.