I'd say try Boktai 1 or 2 on GBA (action RPG). Still, that might be too easy. As for resets, unless you're really bad, you'd probably only reset after boss fights (or the first one around 20 minutes in) for Boktai 1 For 2, there's some forging you have to do after the first boss that's pretty much based on RNG for the result.
Boktai 1 any% is currently 1h42 ~ 1h55 As for 2 any%, iirc it's around 2h ~ 2h10
Oh btw, to play these on emu you'd need to use patches, they can be found on the leaderboards though.
I'm starting a Jimmy Neutron: Jet Fusion speedrunning community atm, the any% WR is about 4 hours if youre interested it is a platforming/puzzle game, i think the speedrun is fun but youre welcome to join, its definately in the beginning stages since I just started it up less than a week ago.
It's a shade longer than 5 hours, but I recommend Lego Star Wars TCS. The any% runs usually go about 5:30-6 hours for a beginner run, and after that you can shave off 2 hours of that and the Super Stories vary but usually around 20-25 mins. There really aren't any skips, and it's really just about optimizing your run
^Any and all of the TT Lego Games are at least 1 hour long. Some have bigger communities than others, some have more skips than others.
Mario RPG is about 3-5 hours when you start, and rewards you for practicing a lot.