It may not be as perfect as you'd hoped.
The problem with Dell (and many other laptop manufacturers) is that they load these restore disks with a load of junk software on them (the same stuff you get when you first buy the system) - if you've no probem with installing that then this will be the easiest option, but it can be a pain to remove it all (and it'll never work quite as well as a clean install)
A completely fresh windows install will be much cleaner, but will take more time. It realy depends what you're hoping to achieve by wiping it (why are you formatting it all and starting again, out of interest?)
If this is something you do regularly you might find it useful to set the machine up with Windows and its drivers etc and then take an image of it - depends how techy you are but it's not a massively complex procedure - there's a few examples of free software that can do it here:
http://www.techsupportalert.com/best...ng-program.htm