* Home Premium is definitely a nicer package as it includes Aero (including the Glass look), premium games, Media Center, and automatic data backup.

* There is always the chance of the upgrade process glitching, but you don't have to worry about compatibility issues since it's still the same OS. That greatly reduces the chance of complications.

* Before upgrading make sure your computer can handle Home Premium for it has increased system requirements, particularly concerning Aero, DVD maker, and the Chess game.

* One Care is not a product I'd recommend at this time. It's a nice comprehensive suite for those looking for security protection, but it is not a finished product. It has one of the lowest detection rates when compared to competing products and even those who worked on One Care have publicly admitted it should not have been released when it was. Personally, I'd stick with the free options you have installed and add a firewall. You can click here for a list of options.

Hope this helps,
John