Yes, get it. Those types of bikes, old steel, rigid, are great values, fun rides, and incredibly versatile. You can, obviously, do mountain biking on them, but also commute or tour, if you put on slick tires. I have something similar (old Specialized Rockhopper, basically the same), and I ride it pretty much everywhere. If it fits you, and isn't in horrendous condition, pick it up and get it checked out and tuned up by you LBS (local bike shop)