I think what you are looking for is Sysprep. you can use the factory reset feature to "scrub" user profiles and give the user an "Out of Box Experience" (OOBE) Upon first boot it'll ask you all the setup questions it did when you first bought the computer. Make sure the laptop has the Genuine Windows sticker attached it has the key you'll need to reactivate windows.

http://technet.microsoft.com/en-us/library/cc766514(v=ws.10).aspx

Before going that route...

Usually Malware is hiding in a randomly generated folder within the username folder (C:\users\username)
Often times it is in the temp folder. Try these steps:

Go to the control panel> add remove programs and uninstall anything suspicious, unwanted or installed on the same day you started to have problems.

Close all un-needed programs including the ones in the system tray (near the time -lower right)

type %TEMP% in the windows search found at the bottom of your start menu. Delete all of the files and folders you find. If some folder/files wont delete open sysmanager and try and close any running services that are using the files that will not delete.

Delete files found in the C;\windows\temp folder
Check the C:\windows\tasks folder and delete any suspicious task
in the start> all programs> start up folder delete any suspicious programs

type MSCONFIG in the windows search found at the bottom of your start menu. go to the startup tab. Uncheck anything suspicious. Google questionable programs, look were they are running from, and see if there is a manufacturer listed.

If all else fails, create a new account with admin rights. log in under the new account. If the malware is gone, copy the My Documents, pictures, videos, Desktop, and favorites folder to the new "accountname" folder.

Louisville slugger?

Should give u the option to restore or repair from the restore feature. Does the computer have a restore partition on the hard drive? U can check for this under my computer. Some times u can do the full system restore from there also. If u don't have the restore partition on the drive. Just pull the drive and put it in another computer as a slave drive and format it from inside Windows

Try this I believe its f8 on boot then factory restore or repair here's a link
http://www.dell.com/support/troubleshooting/us/en/19/KCS/KcsArticles/Art...

Go online and download a copy of windows xp.You will also need the xp crack to activate it.