First, if this has been addressed before I apologize. I tried searching the forums, describing the problem as best as I can, but when you aren't sure what is wrong it's hard to look intelligently for an answer

So, 2 questions:

1. When I have the bike shifted onto the smallest ring in the back, the chain slips off and gets stuck between the chain ring and the frame. Is there anything I can easily do to fix this?

2. What is the least likely way to damage the frame for me to get the chain unstuck?

And, I suppose, 3, with the Shimano 105 shifters where you push the small lever in to go to a smaller gear and the larger lever in to go to a larger gear, is there an easy way to tell what gear you are currently in?

Thanks for any help