The MegaMan series is one of the best side-scrollers to hit the NES (or any system... well, next to the Castlevania series).

Yes, MegaMan 2 was the best in the series. Well, considering that I only beat 1, 2, and 3; I played X for SNES; and I think I played 4, 5, and 6 for NES or something. The music in 2 was so well done. Hip Tanka (if I remember correctly) did the music and is The Man second only to the guy who does the Final Fantasy scores (which, as a trained musician, rock my world).

Haha, I used to draw Mega Man characters and Mega Man levels while in class in grade school. I had the style pretty down and thought up some cool characters. If I find the drawings, I'll post some scans.