I'm not comfortable with all the choices on offer, but Safin's AO win over Federer picks itself (Federer's only loss in a fast Slam in the last three years), and out of the three Masters Series won by Nadal in a fifth-set tiebreak the first Rome final against Coria just edges it as the most dramatic of the lot, longer by nine minutes than this year's epic.
I'm not sure whether Nalbandian's "hard fought" 6-2, 6-2 victory over Ljubicic in Shanghai last year really qualifies as one of his most inspirational wins, it was certainly a terrific performance though. I would almost suggest that his win last year over Hewitt in DC is analogous to Hewitt's own DC victory over Guga - to beat such a great player, and great DC performer, on their own turf in a convincing straight sets is a remarkable accomplishment.
I agree, I had trouble choosing Nalbandians 2nd match. Off the top of my head, I did not remember a good Nalbandian epic, so that match just occured to me. Ljubicic was playing amazing last year in Indoor surfaces. So it was a good win for Nalbandian, maybe not his best, but worth mention. But my bad on saying "hard fought".
I know, these options are fiercely debatable, but these were the options I came up with, sure there are other great memorable matches from these players, I am just mentioning a few.