AD&D Campaign Module Order
This question comes up a lot, so here's my current list of what I'd run in order for a 1e or 2e AD&D campaign from existing modules:
Spottle Parlor (Basic very short game, could come after Zenopus from Dungeon #12)
Tower of Zenopus (Basic sample dungeon, available free converted to 1e/2e)Â
B2 Keep on the Borderlands (Basic again, there's total conversions out there)
T1 The Villiage of Homlett
C3 Lost Isle of Castanamir
WG4 Forgotten Temple of Tharizdun
S2 White Plume Mountain
G1 Steading of the Hill Giant Chief
S4 Lost Caverns of Tsojcanth
G2 Glacial rift of the Frost Giant Jarl
S3 Expedition to the Barrier Peaks
G3 Hall of the Fire Giant King
D1 Descent to the Depths of the Earth
D2 Shrine of the Kuo-toa
D3 Vault of the Drow
S1 Tomb of Horrors
WG6 Isle of the Ape