Probably either What's My Name (being the first single) or Lodi Dodi (being the song we all rapped on the bus on the way to basketball games at that time. Listened to a ton of rap before that but never really went out of my way to memorize any full songs. But then Doggystyle changed everything as I memorized the entire album (including skits), and can still recite it front to back to this day. Now I probably have like 1,000 rap songs memorized, not even a lie. Full albums by Common and Snoop, and countless songs by Outkast/De La/Tribe/everyone else.