Performance:

The first thing any OS aficionado does when he installs an OS is check how it performs on his hardware. Vista performs well, but it sure takes its liberty with the hardware. Fresh install size was 11GB. I wouldn’t begrudge it 11 GB if it had one of two things. (1) a LARGE quantity of preinstalled programs, or (2) a very large quantity of preinstalled programs. Neither is true.

RAM usage is another black hole. On a fresh boot, Vista is using 50% of my RAM (883MB), not counting cached files. After a couple hours of sub normal use (just web browsing and playing a few games with WMP running), Vista was using over 60% of my ram, or about 580MB, and rising all the time. My current usage in Kubuntu is 480MB. But this is after 2 days of being on, being suspended, and running Gimp, OO.org, looking at pictures, web browsing, evolution email, beryl, and most of all running KDE. I have never seen Kubuntu use over 500MB of RAM (400 being the norm), and have even run Kubuntu quite successfully on 256MB. Vista was also using half of its allocated page file( think swap). While this does speed up the OS, it increases disk usage which is NOT a good thing on laptops.

Configurability:

Preinstalled Apps:

More Here

(Part 1)