hum; any channel will work, but that's the least important issue to be solved.
for that issue, get a copy of Network Stumbler; it will discover ALL wireless
systems in your environment AND report the channels being used. You should
opt for a channel that is NOT active already
I assume you have it installed and it is running; if not please report your status.
If it's running, the be sure to consider these points:
1) change the default password
2) change the SSID
3) STOP broadcasting the SSID [ this forces you to know it to make the first connection]
4) get the MAC addresses of ALL your system (via ipconfig /all)
5) restrict all access to KNOWN mac addresses
6) enable encryption and document your access key
7) BACKUP the settings (if available)
ALL this work should ONLY be performed from a WIRED connected system.