Platformers are usually the games that has these mascots and stuff geared towards kids. They frustrated the hell out of me as they usually had cheap deaths or something rather unfair. I always had to use game enhancers on them as I never really enjoyed playing them without the extra help to make the game easier. Recently I'm playing the New Super Mario Bros. Wii and I am tearing my hair out over some of it as there is no game enhancer for the Wii. I don't see how any kid could seriously play most Mario games as many of them just challenged me too much.
I'm trying to think of platformers that were NOT too hard for me from the 8 and 16 bit classic era and I'm having a hard time. I went with all the popular titles and most of them required me to use a game genie and a Nintendo Power to beat.
Before that era, I remember annoying kid bait stuff like Commodore 64's Transformers and Colecovision Smurfs that are still impossible for me to beat today. Yet I somehow I was able to understand and beat E.T. many times as a child of 10. How very strange.