how to do a clean install of a new operating system

[viruses]

I am thinking of getting windows 7 next month, I want to know how do I install it on my vaio laptop which has got vista premium.
also I want to upgrade my compaq laptop which has got windows xp to windows vista home by doing a clean install.please help

 

[Amir.php]

Just take backup of your needed files....Format and do a clean install of windows 7.
It is not so tough....though if any error or problem then specify here.