Smash it with a hammer.. Buy a new 1..
lol. Seriously idk bout lappy's but usually when it reboots on the load up screens it says "if you want to go into recovery mode press f9" or something like that and you have the option to restore the thing back to factory settings which will wipe everything. But thats on an XP home edition.. so may be different for yours.
are you trying to get rid of your porno collection?
ive got a copy of xp ready to go on