It usually reboots by itself when a blue screen pops up, but on default, XP hides the blue screen and reboots the pc automatically.. Right click My Computer -> Properties -> Advanced -> Startup and Recovery section Settings -> Uncheck Automatically Restart in System Failure section.. Next time something goes wrong, XP will show the blue screen and then u can restart your pc manually.. If a blue screen pops up, note what its saying and if its possible, post it here so we can analyze it .. As for the loading pc when opening files or music, it could be just the indexing service that basically indexes the files so when u use the search function, it completes faster.. If you defrag your hdd, it will probably be faster.. It could be also like that because of an old XP installation (if you haven't done a fresh install lately).. I had an XP installation once that restarted explorer.exe all by itself.. Try the thing with the blue screen and defragging your harddrive and post back here