If you have the opportunity, check out some local shops and see if they have any demo days or anything coming up. That way you can try a bike out and see what best suits you for your needs on trails.

If you're not looking at doing any of the jumps or anything, I'd suggest just taking your hybrid out on some flat, easier trails just to get a feel for trail riding. That way you'll also know if it's something that you're going to like or not.

My father made the switch from road biking to mountain biking at 56, and although he finds it different, he is having an all around blast riding some of the trails with me.

Happy peddling, pal!