Yeah you should be sure that you have your OS disk before you reformat and also make sure that you have a disk containing any drivers that you need (you have drivers for your sound card, graphics card, basically anything connected to your computer) Once you have all your stuff together the process is quite simple I know I have done it a few times. I don't remember the exact process of the top of my head but do a search on google or im sure www.ehow.com probably has some instructions to follow.