At move 39, I thought I had enough protection from my pawns. I really didnt have an option but to play D, or try something. Did I?

Good question, Moe.  I've reviewed this game several times.  Avsig's first mistake happened on move 8 when he castled queen side.  That move lined his queen and rook along the black file, something I didn't notice until move 11 when I moved my Bishop to g5 pinning his queen to his rook.  There was a few moves that he either should have made or, in some cases shouldn't have made which I'll gladly go over if anyone wants me to, but what should he have done on move 39?  Obviously Qxa4 cost him the game a few moves later.  I'm not sure what his best play would have been, but if I was in that situation, I would have gotten my queen behind the pawn being pushed down the h file so it couldn't be promoted to yet another queen.  Then I would have pushed my own pawn along the a file.  I think no matter what he did, Avsig was going to lose the game at this point unless I made a major blunder, which I do a lot, but I would have had to work a lot harder for the win.

Should he have moved his King on # 39 ?