back up all of your data(music,documents,videos)before you do this..if you can't boot up then use ubuntu,slax or other types of bootable cds. also be sure to download the drivers from dell.com put them on a flash drive just in case automatic updates don't get it
to set it back to the factory setting you are going to have to get a xp installation(asuming it is xp,or what ever disk came with your comp)the disk should say operating system on it.what you do is put the disk in and boot off of it.if this message don't come up 'press any button to boot from cd......' then your going to have to go into the bios and change the cd drive before the harddrive.if the message does come up hit any button and wait for the blues screen.after it is loaded hit enter f8.if a screen says existing operating systems hit esc(on that screen there is a option to repair the os but you have to know th command lines to do so).if not and it goes to the partion screen then delete the existing partion and create a new one.to
do so go to the partion and (delete)hit d L enter.(create)c enter. after you have formed a new partion hit enter....it will format the drive(delete everything)after it is done formatting it will start to instal the os.in
xp it will stop 2 times for your input.after everything is done loading you should be able to custamize everything and install things.in
the bottom right hand cornor there should be a marker telling you to activate windows.click it and use the product key
on the side of your comp(laptop under it)if there is none there try keyfinder.i will email it to you if you can't find .also be aware that you have to reinstall office, antivirus and other programs. so make sure you have all of the cd's.