Some people would consider that a long run :P
Chip and Dale on NES I got a time of like 20 minutes on my first try while very drunk so that might interest you
Star fox 64 is pretty short and easy, and there are tutorials for almost every category. ~30 mins for a first Any% run.
Jazz Jackrabbit 2 is short and also relatively easy to learn. 30 minutes at most, but 25 mins if you wanna put a decent amount of effort into it (and sub 20 if you want to put a great amount of effort). There's also the side episodes which are at least twice as shorter, and have no records in some categories (The Secret Files, the shareware episode, the xmas episode).
https://www.speedrun.com/Code_Red#Any Pretty fun run, good story as well :)
I moderate a bunch of short games: https://www.speedrun.com/user/Oxknifer/info
Happyland adventures. At start will be like 15min for orginal and 30 for xmas edition (which is better)
chibi knight. 100% takes like 13 minutes and any% can be done in around 4 i may be biased because i run it a lot. but it is short, sweet, difficult, and definitly skill intensive
gotta love having a 1 year old thread being necro'ed a third time
This thread is like the villain in a horror movie. It doesn’t die unless you cut it’s head off