if it's a desktop computer and the router is next to the PC then don't make it wireless!!
Wireless is not a fast, stable, or secure as wired connections, it's only benifit is mobility, as you are unlikely to want to pick up a desktop computer, monitor and keyboard, mouse and walk round the house using it you have no need for wireless at all!
Wireless seems to be the new buzzword for people and everyone seems to think they need it... A lot of people don't though.
do as DrFilth says and use the cable that comes with it.