xp boot up help plz..

HEY ppl

My xp is not loading up after the xp logo how can i fix this i have got an xp cd i have gon to repair abut it ask for an admin password i dont have one on my pc wot cod it be..

When it asks you for a password and you do not have one, have you tried just clicking through it?

And also, it sounds like you've damaged your system files.