I think this thread is dead, but here's my 2 cents worth. I work on mowers and have the same model right now. It's virtually identical to most front wheel drive models in that the biggest things that goes wrong with them is 1) the drive belt - usually an easy fix 2)cable rusts and sticks/breaks - also easy and 3) the axle bearings going to the front wheels dry out and lock up from moisture. If the front wheels won't turn with the drive mechanism disengaged the bearings are probably rusted stuck. Usually this means getting a new mower, but if you are really stubborn you can try to get new bearings and install them. Probably have to cut the old ones off...
Rob in NC, June 2009
