arsatweb

One thing I've done if I'm dealing with an unstable or low-quality wireless connection, is to disable timeouts on Firefox.

If you type 'about:config' (I'm using FF3, so if you're using 1/1.5/2 these settings may be different) in your browser bar it takes you to the Firefox settings page.

In the Filter box type 'timeout' and it'll show all items with timeout in its name.

You can try increasing numbers to attempt to hold the connection longer while waiting for a response. Depending on the timeouts and what you're doing when they occur you'll want to change different options. (i.e. browser.download.savelinkasfilenametimeout is pretty self explainator and you wouldn't want to touch it if you're having issues loading a web page, but if it's timing out on a download then you'd want to try this setting).

This is a good fix in the event that it's a touchy connection, but it sounds like it's more than likely the sites themselves. When they don't load, you can also try to ping them.

Go to Start > Run
Type cmd and hit enter
Type (without quotes) "Ping www.whatever.com"
If the site is unavailable, the ping will time out as well.