When I was in need of Windows Media centre for my PC I downloaded the software through the internet (PM me for site) and used my computers product key which was on the side of the tower. Now that product key only works on whatever it was on originally, for example WMC for WMC product key. Service packs don't make a slight difference to key usage.
I'v heard windows 7 is rubbish and not worth getting, for simple people im told...
If you want to make a back so you can restore id advise Paragon
http://www.paragon-software.com/home/db-express/
Works great with Win7 and never let me down.
And why would you need to reinstall?to fix problems via the repair console?
If so press F8 during start up,then you can boot into the Repair Console that also comeso n the Win7 disc.
One thing that annoys me is the way they dont supply the installation disc with new pc's anymore,i mean you paid for it after all.
as Dylan said, most laptops don't come with the CD's anymore.
the usual way to access the recovery partition is to keep pressing F8 when booting and choose repair your computer.
from there you should see a way to recover to factory settings. usually the last option after the default windows recovery options
failing that it's usually an F key before windows boots, look for a prompt when the manufacturers logo displays.
Do i have to actually create a Backup or is that something thats always on the system? Forgive me for sounding dumb... extremely tired