WiFi Problems?

Heyy haven't been on here for a while, thought you guys might be able to help me =\.

Yesterday we got a BT HomeHub to replace our old BT one that we got in 2004 which is now rather useless and obselete.

Installation was fine and everything but I think there's a connection issue with my PC? The Internet works perfectly fine on my sisters laptop, brothers PS3, my iPhone etc, but for some reason my computer just doesnt like it =|. There was nothing wrong yesterday when the old router was being used and my PC is pretty new.

Pages dont load, or if they do it takes about 5 minutes and alot of the time most images dont show. Not sure how to explain it but if anyone understands, any clue to as what it could be?

I even tried reinstalling the OS (partly becuase I needed to anyway) and still got the same problem.

I'm guessing it isn't the hub. everything is connected via wifi and everything else works great. got any ideas?

Are you connecting wirelessly or wired?