Wired Connection Slower than the wireless connections

Here's the situation. There are 4 computers in the house connected to the net with Verizon dsl and a Westell gateway. 2 desktops are hard wired to the router with ethernet. The laptop and another desktop are connected wirelessly via the laptops internal wireless device and the desktop by a Belkin usb adapter. The thing is the wired connections are dialup slow when pulling up web pages and streaming video. The wireless connections seem to run as designed. I always thought it should be the other way around. any ideas on some router setting maybe that I need to change or something. I'm out of ideas and my usual help sites have been no help. Thanks for any input

Thanks Roxy. I thought about new cables as my first option. The ones I'm usiing are a bit old.