Some people do have issues with wireless, but if you stick to the well known makes there shouldn't be much of a problem.
Interference from some devices such as microwaves can have an effect, but it is much more likely that your building environment will affect things. Lots of steel in your location will drastically cut down on signal strength, but you can always experiment with antenna placement or alignment.
Keep off the default channels - every man and his dog use these, so it's little wonder that interference can occur if more than one network is in the same area.
Go for a tried and trusted 802.11G network with WPA encryption. Keep to the same manufacturer for your AP and NICs and you should be fine. Any of the newer 'turbo' or 'pre-N' systems may work, but I'd avoid them until some standard has been ratified.
Make sure you take all the usual security precautions (change the SSID, don't broadcast it after setup, don't allow wireless setup, use WPA encryption & MAC address filtering) and you should be fine.