Do you have a rescue CD from which you can boot? (The
SystemRescueCD is one of many possibilities.)
Boot from a rescue CD and run
e2fsck -v /dev/sda2 The
-v option will generate a lot of output, but you should be able to see what is happening at 43.1% when the program seems to stop.
Note that the "percent completed" computation seems to be based on the
volume of work, not the
time needed to do the work. Thus the "stand at 43.1%" may only be a "long pause at 43.1% while work on something is done."