ShinHakkaider
Adventurer
For me it's either T1 - The Village of Hommlett or B2 The Keep on the Borderlands (not that B2 actually HAS much of a plot. In that way it's PERFECT for a starting adventure). I've used B2 as a conversion example for various versions of D&D when I played D&D. I've always felt that if I can convert and run it with whatever version that I'd be able to run that version of D&D with few issues.