I am a newbie and excuse my ignorance.I have downlaoded the Mess 0.64 and I have a game from MSX direct that has a >DSK extension on it.Can anyone give me a clue how to play it .

If you are just starting with emulation, PLEASE try something else than MESS. There are more user-friendly emulators aroudn, like paraMSX and NLMSX. RuMSX has a very intuitive user-interface, but it's emulation is not as good. For more info, you can read the Emulator Comparison, for instance...

I think you can get a .DSK running on NLMSX without further explanation, but if you have more questions... don't fear to ask!