It would only make a difference if you were using your computer's sound card and it's line-input. That's normally a stereo 3.5 mm TRS jack and if you plugged a (mono) guitar cord with a 1/4"-to-3.5 mm adapter into it, only the left side would get an input.
If you tried recording a stereo input, there would oly be sound on the left side of the track; the right channel would be blank.
If you had a stomp box with cool stereo effects, you might want to record on a stereo track.