Open Question: How can I set my LG Wide screen monitor to a regular screen mode to play a non-widescreen game?

How can I set my LG "FLATRON L222WT" Wide screen monitor to a regular screen mode to play a non-widescreen game? Alot of old games I wish to play do not have a widescreen resolution setting, how can I make my screen like a widescreen TV with bars on the sides?