When setting up a wirless router we forget to set the DNS servers and let the ISP set them which can slow down the connection.
A lot of times a slow connection is realy the DNS servers, your are using - are overloaded. Most isp's run a standard BIND server that is very veunerable to floods that can be common with older Linksys routers.
http://www.DNSServerList.org has daily updated servers that are open to the public.
Try changing your DNS servers on your router to these.
Also note that if you have a Linksys (Or other router with three DNS slots) populate all three.
Helpfull sites.
http://www.DNSServerList.org
http://www.Open-DNS.org
http://www.IPGeoLocator.com
Enjoy
QW