This is brilliant.
This is really impressive work. MegaMan controls very well (or at least as well as is going to happen with a keyboard) and movement holds effectively true to what it would be on the NES. Lots of flash games that attempt to be MegaMan or Mario or whatever else fail to capture the correct feel and timing with movement and jumping and this one hit the nail on the head.
Ghosts 'n Goblins seems like an odd choice to pair it with and the whole thing makes literally no sense; but that just gives it more charm. This is absolutely spectacular work. Don't ever let anyone tell you otherwise.