the 5ms is the response time, really has nothing to do with refresh rates. While not all LCD's are locked at 60hz, any monitor's refresh rate ability varies with the resolution you expect it to output.
BSkip22 is correct that a 60hz refresh rate isn't important on LCD's, because they don't suffer from the flicker effect so prevalent with CRT monitors. If you think the 60hz refresh rate is limiting your framerate, just turn off vsync in your game, although 60fps should be sufficient for just about any game, I would think.