If you can run the WiFi card software (instead of XP Zero Admin), you normally have the option to run a "site survey" - which should give you the name and channel of any other networks it can see.
Microwave ovens generally interfere with channel 9 (badly) with a spread to 8/10 and top a lesser degree, 7/11.
The channels also spread, so in the 1-11 channel space, the normal channel choice is 1, 6, 11, - compromise 4 channel plan is 1, 4, 7, 11
http://www.btinternet.com/~duncan.ja...avelength.html
If all equipment supports the ETSI (1-13) channels, then I'd push from 11 up to 13.
Video senders also share the same band, typically with 4 channels (A-D) across it.
A - CH1-3
B - CH5-7
C - CH9-11
D - CH12-14