Q: Wi-Fi Connectivity issues

I have recently been having connectivity issues with my iMac.  I utilize an airport express tied in to a cable modem. My wi-fi network works great with other devices (e.g. iPad); however, on my computer, pages typically don't load at all.  I find that I have to turn off, then back on, my Airport express utility to get the pages to load.  I have done all current updates provided by the automatic updater and just re-installed my Airport Express drivers thinking that would help.  I have OS X 10.6 update 17.  I am now at a loss of what to do.  Any help is appreciated.