If its a Contitech timing belt on there you went way too long leaving it on there (41 000 km's). I just changed one today on Brandon Daum's talon tonight and i would say it had less then 10 000 km's on it and the teeth were separating off the belt and small pieces of the belt that turned to dust were everywhere. If you have a contitech belt on there i wouldnt leave it on more then 15- 20 000 km's.
Even a stock OEM belt i would change every 50 000 km's knowing how hard these cars are on belts.
But if the belt still looks fine (sometimes the teeth only strip off one part of the belt and you dont notice it right away)
and you say you have 150 000 miles on the car? Its never too late or two early for a 7 bolt to crank walk. I have seen several with crankwalk problems make it over 200 000 kms and then crap out.
Start with getting the lower timing belt cover off and lining up all the timing marks... It may have skipped and now the valves are hitting the pistons causing it not to turn over. If you take the lower cover off and still cant move the crank, then remove the tensioner and slip the timing belt off (or just cut it) Once the belt is off you should be able to turn the crank either one way or the other if it is hitting valves...
Either way sounds like your probably going to be looking for a new engine.