I have Windows Vista Business preinstalled on a Sony Vaio laptop I bought 2 years ago. I never made the backup/reinstall DVDs because I am a lazy wotsit. I have the product key on the Microsoft certificate on the underside of the laptop. The computer is 2ghz centrino duo with 2gb ram but runs v.slowly these days.
1.1. Can I install from a friends DVD of Vista Business SP2 and just put in my product key?
1.2. Is a fresh install likely to speed up my machine?
1.3. After backing up my files, should I format the hard drive or just do fresh install without or what option should I follow?