I too had hoped to skip Vista and go straight to Windows-7 BUT my motherboard died last week and now here I am on a 64-bit Vista machine. Seems OK so far but is a little frustrating when all of the software I used to use and want now doesn't work (even in compatability mode).
I have problems getting my old Marine Aquarium 1.1 to run - it installs fine BUT will only run manually and is not present in the Screensavers list (see other thread). However, I have downloaded the demo for Marine Aquarium 3 and it works perfectly. So other users should not be afraid of Vista the upgrade of Aquarium is fine - absolutely stunning on my new 22 inch LG Flatron screen.
By the way, I too have ended up turning off UAC - a royal pain in the backside - a shame the implementation was so poor as the basic idea is good.
Steve