Try changing the Channel number in the router's wireless settings, which might help to avoid lost connections. The other adapters in the house should pick up the changed channel without a problem.
If that doesn't work, try deleting the existing 'profile' in the adapter's software and go through the procedure to "Connect" again when a new profile will be created.
I'm actually a great believer in using Windows' own "Wireless Zero Configuration" to manage wireless connections, rather than third-party software supplied with the adapter. It is much more straightforward and seems very reliable.
If all else fails, another Belkin USB WiFi adapter might be the answer, installed with "drivers only" and using Windows' WZC