I remember aggressive (red) NPCs in the starting zones.
I remember Hunter / Warlock pets running away with a hostile NPC due to a bug that existed for years.
I remember whispering random warriors I found in /who asking them to tank a low level dungeon.
I remember that a friend who was at my place started to drag all the useful abilities I never used out of the Spell Book onto the bars when I told him I had a hard time leveling.
I remember having to alternate between Dustwallow Marsh and Stranglethorn Vale because I would run out of yellow/orange quests.
I remember going to Goldshire often when I was low level just because there were people. A lot of people. Just being there, duelling, talking.
I remember that there was a ship from Darkshore to Menethil Harbor, instead of from Teldrassil / Darnassus to Stormwind.
I remember when Innervate had a 6 Minute cooldown.