You have to reinstall all the Dell drivers also, and their updates.
You can do this my entering your Dell computer number onto the support.dell.com site, showing all the Dell specific drivers to one folder, then burning it to a CD and installing on the target computer that way.
Plus you are going to need to install the service packs off the Windows Update when you are up and running.
oops, sorry for the typos....but you get the idea...you need to install all the Dell drivers...I would get the updated versions off the website