Left 4 dead 1&2, Halo 1-3 + Reach. Man I miss co op games with friends on split screen. Do modern games even have split screen options outside of Nintendo titles?
+1 for the Bungie Era Halo franchises, IMO they have one of the best stories, and they honestly all hold up well. Plus you have so much that you can burn through with friends, and it has such deep lore you’ll be chatting for hours.
1, 2, 3, ODST, and Reach are all great for this. 1 and 2 support 2 players. 3, ODST, and Reach support 4 players
Baldur’s Gate 3, good for up to four player coop.
Borderlands 1 & 2, too.
I’d suggest Planescape Torment over BG1 or 2 - if you’re willing to work with archaic UIs, Torment is amazing.
It Takes Two. Phenomenal game, decent emotional story behind it
Portal 2 has a very fun co-op story mode. In fact, I’d recommend the solo story mode for both Portal 1 and 2 as well. One of my favorite video game stories ever.
I haven’t played them myself but I believe both It Takes Two and A Way Out were designed to be played in co-op only so both their stories should be good.
Portal 2