I was born in 1988, so needless to say it was impossible for me to experience the original Donkey Kong in the arcades in 1981. Nintendo did release Donkey Kong on NES later on, and I did play that version via the Gamecube version of Animal Crossing which let players find NES games as unlockable gifts. It was Mario's first video game, so it's a must for every gamer.
The first thing I noticed is how it's not like Super Mario Bros or even Donkey Kong Country. The stages are short and simple, and Mario moves very slow and can't jump very far. Of all the 3 stages, I think the first stage is the best. Just so classic in my opinion.
But do like how every stage was different. It took me quite a few tries to figure out the correct path for the 2nd stage.
But sadly the NES version only has 3 stages. The arcade original had four, so one never made it. The game was meant to be played over and over kinda like Pac-Man, but I could never do a marathon.