Games from the Amateur Teams

It was a busy week, so I am just now getting around to posting some games from the World Amateur Teams last week.  Our team finished even at 3/3, but we stayed in the main room the whole time and rose as high as Board 15 along the way.  Though Fritz says my games are riddled with errors and inaccuracies, I still ended with a decent score of 4.5/6 and will likely gain a few ratings points.  Almost all of my games as both White and Black began 1.e4 e5, which is a bit odd.  I have annotated my two games with the Urusov Gambit (about which I've written a bit) and my three games playing my Black Fianchetto System in the Open Games (on which I have written a Part One and Part Two, and seems it's about time I got around to the other parts).  


Every time I play in a tournament, I wonder if I couldn't be spending my time better.  Then I will play a good game or even make a single good move, and the pleasure of winning seems to erase all second thoughts from my mind.  The following are a couple interesting positions -- one of which I have already posted.  Black to play and win -- and both from Black's perspective.  The "solutions" now are posted among the annotated games.

Xu - Goeller
Black to play and win.

Kolker - Goeller
Black to play and win.

I'm sure it pains him to see it in print, but I could not resist annotating a game that Don Carrelli played in the last round.  He was filling in for Ian Mangion, who unfortunately fell ill on the last day and couldn't play.  In the diagram below, his opponent made a brave and fateful decision.  What was it?

Carrelli - Xu
Black to play.  What would you do here?