Carnage is right. Just depends, but toshiba does the same thing. Where if you boot from the recovery CD it starts to go straight into recovery mode to wipe the hard drive and reinstall NOT JUST the OS, but the bloatwear and software that originally came w/ the laptop.
Get your hands on a copy of the same OS (home or professional) then do a repair install. Some installs you cannot do a repair install on. I've seen a few laptops where you follow the same exact steps going through Windows setup and you get the to point where you press R on the partition you want to repair and there is no R to press.