Thinking about picking one up while I still can.
Would get a 3DS XL, but they quit making them.
Anyway, will all of the 3DS games work on the 2DS, and are there some pretty good games?

I had a 2DS XL that I bought a while back to play some of the games. I had all the big titles like Zelda, Luigi's Mansion, several Marios, Metroid, Pokemon, etc. Every game worked fine, just in 2D (which I never really cared about 3D anyway, IMO 3D is a gimmick). Some of the games like Zelda used the 3D as part of their puzzle dynamic, but to be honest you really don't miss it as the puzzles can still be solved without it. They might be a tad easier with it, but it doesn't break the game.

I've since given my 2DS and all my games to a little nephew as I wasn't using it anymore. He loves it.

I'm glad I had a chance to play those games, but for me personally the handheld was an evolutionary dead end.

Buy a used 3DS XL. Nothing wrong with them as long as they're in good condition.

The 2DS was wonky and hard to hold.  We bought one for my nephew for Christmas a few years ago, I just couldn't stand holding the thing.

Should play all the games just fine.