A standard res game is not playable on a medium res monitor. There are a few models of dual res or tri-res monitors but they aren't very common and you are not very likely to run into one inside a random cabinet. Plus you have the little issue that very few games use 49-way sticks.
Get your model number model off the monitor chassis and google it, you will be able to find out if you have a dual res monitor (probably not).
Basically a Dark Legacy is not a very good choice for a multi-game project. But it is a pretty valuable machine and should be an easy trade for a machine that would be more suitable. If you do want to keep that machine there there are some games that use the same monitor and sticks (that other newer gauntlet, and a few sports games come to mind).
I have Gauntlet Dark Legacy and it uses a Med res monitor, I would like to use this cabinet for other Jamma games.
I know the the Joysticks are 49way optical, but my quesitons is
Can you use a Std Resolution Jamma Game (like NBA jam) with a MED res monitor.
thanks