I would make a partition on your good drive "C" large enough to hold your data on the bad "D" drive. Then I would down load the new "maxblast" software that has a copy utility. (your original software may have it). Then I would try to copy from the bad to the good new partition on the good drive.
Now you will have a good "C" and "D" on the good drive, and copy bad drive "E" to (partition) drive "D" on the good drive.
BTW: even though it is failing, it may still be able to carry out this function. Keep your fingers crossed!
BTW: If it is the HDD controller, maybe you can borrow a bud's computer and plug into his and verify that. Then go buy a new, faster, hotter, sexier MB!