Unfortunately there are lots of features which can interfere with wireless networks - actually older cordless phones (I think 2.4 ghz) interfere with 802.11g networks. Your reliability on channels which conflict with neighboring networks can be an issue - the channel is set in the setup for the router and there are several ones to try - this mostly becomes an issue in buildings like apartments where there are lots of routers in close locales.
I agree with Bert -- wired is the way to go if at all possible. I actually only use my WIFI for my Tivo and Phreesia pads - everything else is wired. I am really happy with having each room have a 500.00 pc and on wire.......
