Move the router instead to a better location for the desktop. Move it away from windows, walls and put it up on the table instead of under a table. Also even moving the desktop slightly can help. Don't put it on the floor or completely enclosed in a desk with sides. Try raising it to a table and see if it improves range. Make sure you are connecting to your own wireless. Make sure your wireless has a distinct name and unique password that only you recognize--not Linksys or any other default name for the ssid and default password. You might be connecting to someone else's wireless with only one bar. Search for available wireless networks to make sure you are using your own.
If that is not any help, buy a wireless N usb adapter for under $15. Like this one. Pair it with an N router and you will get better connection. Check the model of your wireless adapter in Device Manager. It might be an older model with less range. Your router might need upgrading too. The new ones are so much better.