Nightmare.
Wireless N adapters never seem to work with Windows 7 x64. I have now, however gotten my F5D8051 to work so I thought I’d post a quick guide.
1. Download the drivers from here for the Ralink chipset
2. Install the package
3. Update the driver for your Belkin N1 adapter to the driver
4. Click ‘Let me pick from a list of device drivers…’
5. Untick ‘Show compatible hardware’
6. Select ‘Ralink Technology, Corp.’ (if there are two, pick the second)
7. Select ‘802.11n USB Wireless Card’.
8. Install the driver and watch your network stop dropping out!!!
Good luck! When in doubt; get the chipset manufacturers driver!
Chris

Chris123NT has posted a wonderful guide that proves exactly what I thought would be the case but didn’t get round to trying for lack of an x64 install of Vista on any machine, oh, and time!