Congrats! I remember how hard it was to start up again last year after a decade off. I notice you've lowered your seat down quite a bit on that contraption. I would strongly suggest you look into a cruiser or "comfort" style bike to get you started again. You seem to be naturally trying to adjust it along those lines--with the handlebars up higher than the seat. There's nothing wrong with this, but a rock hopper isn't really intended to be ridden that way. I started up on an Electra cruiser and moved gradually to a Marin Redwood, which I've slowly turned into more of a hybrid bike. Only now, after a year, am I shifting to a mountain bike again. Here's the redwood:

http://www.marinbikes.com/bicycles_2...s_redwood.html

As you can see, the bars are up a few inches over the seat. This allows you to stay at a higher angle and was easier on my old bones. On the down side, it limits your ability to use your larger muscles for powering over obstacles and up slopes. It also means you're hitting more wind. But for starting out I found this was not a big deal.

If that one works for you, you're ahead of the game. But you should at least try a cruiser or a Redwood style bike. The cruisers are particularly nice because they're incredibly stable and the Electras allow you to always have a foot down on the ground if needed.