There’s a fairly good chance that the wireless channel you’re using is just congested. This is getting to be a problem nowadays as pretty much every building has its own wireless network and they are all fighting for the same bit of bandwidth (especially when a lot of routers default to the same channel when they are first installed). When Virgin installed my router the wireless signal was so weak as to be almost unusable.
Go into your router settings by typing the router’s IP address into your browser (Google your router make and model if you don’t know it). Somewhere in the pages that come up will be an option to manually set the channel (there are 13 to choose from). Just keep changing the channel (and applying it) and see what difference it makes. You may well find (as I did) that some channels give dramatically better signal and faster web access than others.
