I'm in the US. I'd suggest using somebody I'd trust... like Corsair or Kingston RAM for instance.
Or your local shop - avoiding shipping can sometimes be in your favor.
You can pop out your old RAM, put in the new... and reboot just fine.
And if you're talking about restoring using your original disks, then upgrading to Vista, that's about as close as you're going to get to a clean install without purchasing the full blown Vista since you can no longer "clean install" via putting in your old disk and wiping clean. Stupid move on MS part, but they felt it necessary.
