hmmm, i never heard of the reset button option just turning off the computer. if you have the windows xp cd's, i would just do a sfc on it. just go to the dos promt, and once there put in "sfc" without the quotes.
then put in sfc /scannow
that will do a scan of all the system files and make sure they are not corrupt and in their original condition. if a file needs to be replaced with the original, it will ask you for the xp cd.