About the WiFi being slow, if you only have a few computers on it, it's just as good as a direct cable connection, mostly. A basic setup is just not made for many users. WiFi is not as simple a protocol as the wired connection, it needs to add more error correction, and each device on the same node divides the bandwidth by half that is available to the others. So if you have a 54mb connection, which in real world is about 45mb, you add a second PC, you are at 24mb, another you are at 12 or so, and so on. When you have 10 computers on, you are getting maybe 1mb or 2, plus the lag due to the interference and distance between the computers and the access point.