Here's just a few off the top of my head but for legs you may want to try Squats (barbell or with exercise ball wall squats with dumbells), Leg Press, Step Ups, Lunges, (those are compound movements) Hamstring Curls, and Quadracep Extension, Calf raises (isolation exercises)
For stretching I could continue writing for ever or I could give you this link, it is a great stretching guide for any muscle group you want, complete with pictures and video. check it!
with a solid and consistent strength training and stretching routine, you will not only feel better and perform better on the mountain, but you will greatly, I repeat GREATLY reduce your risk of injury.
Hope this helps!