I love this game - just mostly while wearing nostalgia glasses.
I grew up with Donkey Kong Jr. I had a dual-LCD screen Game & Watch version of its sequel as a child and I fondly remember diving deeply into its old-school patterns of enemies while trying to get the keys to free my "dad" (Donkey Kong himself) from the cage Mario had thrown him into.
Make no mistake, this is an old-school game, first appearing in arcades before ports to various home consoles. It's got the simple, brightly colored retro graphics of the era, and lovable-yet-limited sound effects and musical range.
But that gameplay I loved as a kid still holds true in this Wii U Virtual Console version. That's a testament not just to the purity of that retro gameplay, but also its simplicity. Donkey Kong Jr. needs to leap from platform to platform, grip one or two vines to climb upward or slide downward (two vines are best for ascending, one is best for descending), and leap over enemy crocodiles ("Snapjaws"), birds ("Nitpickers"), or electrical "Sparks." You can collect fruit both for points and to drop on enemy heads. In the fourth level, you have eight different chains to climb with the objective of pushing some keys all the way to the top of the level, finally unlocking your father from his cage. Meanwhile, you need to keep an eye on the movements of enemies both in the air and on the chains themselves.
And that's it. Wash, rinse, repeat, and get slightly more hairy with new enemy patterns on repeated plays. Two people want to play? They can take turns. It's a short game, making pick-up-and-play sessions a natural fit, but only diehard high-score chasers will find longevity in the experience.
Donkey Kong Jr.'s gameplay is still there, and the game presents itself admirably despite the passing of more than 30 years. But it's a small game, a limited game, and a short one. It's not that Donkey Kong Jr. isn't fun. It is. It makes me happy. By all means, put on your nostalgia glasses and the game is a blast, a triumph, and a worthwhile journey to a bygone age. But take the glasses off four minutes later, and while the sense of fun lingers, it's highly unlikely to captivate.