I know, perhaps this should go in the Mac forum, but it's also, if you look at it just right, kind of fun...
We have horrible, horrible internet access at our house. We have two providers, both of which suck. We have a satellite provider with limited daily download allowances and marginal performance, and then we have a "line of sight" provider - no download limit, but very finicky. Right now, we move our Apple airport back and forth, the question is:
Can we have two airports in the house, or will they conflict with each other (same frequency?) ?
Spot false dilemmas now, ask me how!
(If you're not on the edge, you're taking up too much room.)
I guess you can just have two Airports at the same time. It would be strange if it didn't work. Suppose that you and your neighbour both have an Airport, then they'd just work. It would be really nasty if both your Airports then wouldn't work.
As far as I know, Wifi routers use one or more of a whole set of channels, which have different windows in the frequency spectrum. When the routers notice that there is interference on the channels that they are using, they automatically switch to a different set of channels. That way they will both work at the same time, on different channels.