The Lehner Wasserfall Via Ferrata is a really fun climb. It starts out vertical, which, if you've never done anything like this before, is an excellent way to find out if you are up for it. You don't need to be really strong for it, there are plenty of holds for your feet and hands. In addition, the steel wire to clip into runs the length of the route, providing added security (even though falling on a Via Ferrata can still get nasty).
Higher up, there are easier sections as well as more exposed parts. Before long you'll reach the crux: a short overhang. If you don't have the strength to pull yourself up and over, there is an escape route leading around it - but, obviously, it's much more fun to go over.
The scenery is wonderful too, with good views of the waterfall as well as into the Ötztal valley.
Back in 2003, when I just started out, this was my very first Via Ferrata. When I was in the area again in 2012, I climbed it once more - and it was still a lot of fun!