You've picked one of the best places in Europe to go mtb'ing
Leogang.... World Cup standard course and a spiffing bike park to boot. Shed loads of mountains and lots of uplifts.
From Leogang there there is a wikkid day ride consisting of going up in four/five or six cable cars and riding down the mountains, in a great gorgeous "oh my God will we make it before the cable car closes" loop. I think they call it the six cabins or similar. You can get a route map and lift pass from the lift station at Leogang.
Often up top round there you have a choice between fire roads and parallel 'walking' paths from point to point, often on the other side of a ridge from each other. Not all of the walking path is rideable, though you can ride them legally, but they make a nice alternative to fire roads. There is even the odd bit of singletrack hidden away here and there but DO TAKE CARE straying from the main and waymarked routes, you don't know what is around the next blind bend and instead of a berm it may be a ruddy great cliff......
