Yeah I forgot about that Castelvania 2 hack version. I had been meaning on making a cart for it, but I have an Everdrive N8 which lets me play just about anything homebrew (or even most regular ROMs, but I own just about everything worth-while except for a small handful on original carts).
I think my last official count was ~180 NES games, and I mean decent ones, not a crap load of all the el-cheap-o sports carts that are worth like $0.10. Only notable ones that I am missing are Battletoads (I played the hell out of it as a kid, but it is of the ultimate hard as hell games, and I never could get much farther than the 4-5th stages, so I never bought it), Ghosts N Goblins (much like Battletoads, just hard as hell), Metal Storm, and Ducktales 2.