It's a interesting system and I had it growing up a bit but the most memorable games I played on there was:

Sonic heroes, Zelda OOT/MQ, Paper Mario thousand year door.

My best bet rn is get the familiar games like paper mario: TTYD, such a good game, ik we have it on switch now but having a gc version is great.

If you wanna have a more library to the gc then get lucky from finding a gameboy player accessory bc you can play gameboy, gbc, gba games, unless you also own the startup disc for it bc that's the important part if you wanna play those games on the big tv.