Uh oh, Trish invoked me.
OK, seriously as a general rule the first thing to try is update the firmware on the router. If you've never done that before it's much easier than it sounds.
The exact steps will vary per router so I can only tell you how it works with mine but since it is a Linksys the steps should be very similar.
1. Download the latest firmware for your router.
Start here:
http://www.linksysbycisco.com/US/en/support
Enter the model number for your router and search.
On the next screen select Get Downloads and download the firmware.
2. Log into your router. Generally you should do this by entering the IP address in a web browser and entering the password. I believe the default Linksys password is admin (no login).
Once you are in, this is how to do it on mine, again may be slightly different on yours:
Click the "Administration" menu.
Click the "Firmware Upgrade" submenu that appears below the main menu.
Click the "Choose File" button and select the firmware downloaded from Linksys.
Click the "Upgrade" button and wait.
I hope that helps, if I don't check back often enough to reply to this thread feel free to PM me if you get stuck.
Josh