Does the router have an ethernet port so that you can try it wired for a while? It may not be a wireless issue.
Additionally, if it is a wireless issue there are different channels that you wireless can run on. These are numbered 1-11. By default most routers are on 11. Try changing it to 1 or 6.
The channels overlap though so changing it to 9 won't help you because you will get overlap from people using 6 and 11. Everyone usually uses 1,6, or 11 since these are the furthest from each other and helps eliminate overlap.
'01 Bullitt #0054