ok though it has been posted earlier as well it does nt matter either one ask it again or not...
any way the solution is
get one software from petri.com ..and reset your password
what it does is make a bootable floppy and start the computer from bootable floppy and the whole process is self descriptive and finally it allows you to assign new password...
by the way there is one software as well dont feel like it is legal exe which allows to reset xp admin pass logging in as power user...
but earlier method is easy
for it google the tropic of your post..you will have all required links
pritesh i have a shortcut when u start the computer wait until windows login scrren show,then press ctrl+alt+del two times it lead to you a new login scrren then type in user name {administrator} and leave password blank then enter.