JCDEVEN, You can use the original disk to format and reinstall the operating system. You can click the link below for information on reinstalling Windows. Windows Support
When I bought my Dell laptop it had Win 7 installed, but also had XP available.  The system now has Win 10, but I cant remember how to get to the XP system in order to use some older appliations that now work on Win 10.  I havent used the XP part in so long I cant remember how to get there.
Former XP partition