I've been using Windows Vista for over a year since Feb 07. From my experience's with it I can say it's the best OS for PC. Here's what I would like to see in Windows 7.
#1: No more user account control! - User Account Control is annoying.
#2: Better Virus Scanner - Windows Defender Sucks.
#3: Include a Office Sweet - Microsoft should include a free office sweet like OpenOffice.
#4: Better Compatibility - Windows Vista had allot of hardware and software compatibility problems in it's first year of being released.
#5: Only one version - Windows Vista has to many versions, there should only be one version with a customizable installation.
#6: No more Blue Scren of Death!
#7: No more DLL Hell!