Under Advanced - QOS I have the following turned on:
Enable Traffic Shaping
Automatic Uplink Speed
Enable QoS Engine
Automatic Classification
Dynamic Fragmentation
And never have problems with any one network device hogging all the bandwidth. I have a XBox 360, PSP, and two computers that all share the network. Even when I'm downloading large files and reinstalling games from Steam my wife never has problems surfing or playing Everquest 2.