iTunes will not download update (either iTunes versions or iPhone software)

Need some help with a connection problem. iTunes will not fully download either an iTunes update or the iPhone software update. I am quite sure the problem is the wireless connection but I don't know how to solve.

I am running Belkin Wireless N networking with Windows XP Media Center with all updates and iTunes is the only place I have an issue. If I run a hard line to my router and hook to the LAN card, all downloads work fine. If I try to use the wireless, I get this message when I try to get the iPhone software update. "There was a problem downloading the software for the iPhone "XXX's iPhone". The network connection was reset. I get the same message when I try to download an iTunes update.

Any ideas on what to do to get around this?

Thanks for the help.