I have Vista Home Premium. I want to upgrade to Ultimate. If I try the upgrade, and it doesn't work like it is supposed to, will I be able to restore my system back to Home Premium? Or will I lose my restore points?
If you do it through the legal "Anytime" way then yes. But I see no reason... all you get are the "extras" that are useless. Oh yeah and the login screen says "Ultimate" instead of "Home Premium". It's Keyser Söze
There many diferences between ultimate and home premium, the extras are only marketing, you can have virtual drive, in internet access the limitation of 6 will go up to 12, the hard drive encription is possible, ect... But the price is expensive too. Try to find somebody that will sell to you a oem ultimate, insted of a retail copy.
And you get to join domains and you get to connect to your PC through remote desktop. Pretty big features for some including myself.