A planted shrimp tank. Or a single betta. If you have a 10 gallon on hand, why don't you just set that one up for him and scrap the 2 gallon idea. 10 gallon tank will be easier to maintain for a newbie IMO.
I'd just go with a Betta. Very easy to maintain. However, heating would be an issue. As long as he doesn't keep it by the window or doesn't heat his room, it should be fine. Water should be at minimum 75F I kept a Betta in a 2g tank for a little while. As he matures into the hobby, he can always up the tank and/or add to it (nano filters, plants, decor, etc.).
I haven't had any shrimp yet. Thanks I think that would be a fun option too! Once the tank is all set up and cycled I plan on taking him into a LFS and pointing out things he could do and seeing what he likes. I'll be sure to point out the shrimp and crayfish and maybe some snails too. Kinda depends on if he wants to try live plants (which I'm going to encourage lol) or stick with silk/plastic ones
I made space in my large tank for my husband to pick out his own fish. He Loves his Gar and we do all the maintience of the tanks we have together. My husband knew absolutely nothing about fish when we got married. We ended up with a betta as well. But the betta certaintly didn't get him interested.
We actually talked at length about the fish he would like, did some research online. then picked out the fish for the tank together and had alot of fun doing so. It's nice now haveing somone I can talk fish with. He now has a 10, a 20 with his fish in it. and our 75 is a mix of both. the only tank I have now that doesn't have at least 1 fish he didn't pick out is my 40.
That sounds great! I'm hoping in the long run to work out something like that when we are married and have our own place, but for now we don't live together and we are both limited on space. He didn't really like the hobby when I was first getting into it, but has recently shown some interest in it and we are talking about eventually doing a small cichlid set up at his place and I want to do everything I can to encourage this interest. But for now I think starting small to make sure he can keep up with everything (he's a very busy man) is the best plan. And hey, I've been wanting to try a nano planted tank so if I end up with it, cool beans!