EEEEEKKK! My chain came off

[DebW]

Thanks that's what I'm up to now. I'm looking at the Shimano Deore XT M770 165mm 4 arm Crank 22-32-44. Although I don't have clue about the 165 mm part. I just want the EASY gears.

165 mm is the length of the crank arm. That length would generally be for a rather short rider.