The Slave Lords series (A0-A4, etc): This one is what led me to post this since we talked about the Slave Lords recently on Legends & Lore stream. Strangely, I collected the original 32-page modules well after I had already ran 2E Slavers into the ground. I feel that going back to the 1E AD&D originals would be more fun.
Against the Giants (G2-G3): I ran parts of G1 the Steading of the Hill Giant Chief as a teen long ago before I knew what I was doing, but I never really got to the high level sections, Hall of the Fire Giant King and Glacial Rift of the Frost Giant Jarl. Now would be a great time to bash giants!
Lost Caverns of Tsojcanth (S4): This is one dungeon that I know fans like because of the backstory, but I think I tried to run once and gave up because of the mountain exploration. I want to just get to the main parts and run it someday!
Secret of Bone Hill (L1): I have never ran any of Len Lakofka's modules and that's a sad admission given that I met him late in his life and now he is no longer with us. I must run a Lendore Isles module someday! (maybe Assassins Knot as well)
Isle of the Ape (WG6): I'm not sure why, maybe its cause there's a new Kong movie coming out, but how have I never ran this module? Me and my friend Jayson have been monster movie fans since we were old enough to tie our shoelaces. This is on the list.