Since no model numbers I can't see if your router or such hardware has this feature. If you install NETLIMITER on the other machine that should help for now.
My simple home network consists of DSL modem to wireless Accesspoint. One XP Pro SP2 connects to the accesspoint via CAT5 cable. One XP Home SP2 connects wirelessly.
When XP home connects to the Internet and is downloading files (viedo), XP Pro finds that connection is very slow, with web pages taking a long time to load, often getting the "server not found" message. When XP Pro connects directly via the DSL modem, connection speed improves greatly.
My questions- is this normal ? How do I limit bandwidth(with settings at he accespoint ?) to the XP Home so as to improve connection to the XP Pro ?