The monitor is a cheap Acer 19" LCD which supports both 60 and 75 refresh at it's native resolution. The main reason I'd like to select a refresh greater than 60, is because when games are played with vsync on (to avoid tearing), the frame rate delivered by the video card is often (depends on circumstances) limited to half the refresh rate. Unless the video card is stout enough to provide the full 60 fps, which mine is not. So with a refresh rate of 60, games like Crysis are locked to 30 fps on my system. If I could run the refresh at 75, then I'd be seeing in-game framerates more like 37-38, a pretty good increase. In short, a higher refresh rate should mean a higher fps rate (when vsync is on). If vsync is off then the refresh rate won't matter.
Triple buffering can improve frame rates when vsync is on, but as far as I can tell, DX10 games don't allow triple buffering either. It's like Microsoft hates gamers who play with vsync on.
Somebody asked about my motherboard, this was a prebuilt system that came this way and could not be reconfigured. It's kind of unbalanced because it has a pretty stout CPU but a less-than-current video card and a budget motherboard. Price was right though.