To make stuff less mystical, zone-dynamic_##.log are from each dynamic zone (sounds like you have about 20 of them, you can change this in the DB, testing wise you won't need more than 5, actually server you might need more)
The rest of the numbers are PIDs
eqemu_<executable>_<PID>.log are the logs for that executable (zone, world, ucs, etc)
eqemu_quest_zone_<PID>.log is for that zone's quests
eqemu_debug_zone_<PID>.log are just debug statements, this is mostly to help you debug whats going on.
eqemu_error_<executable>_<PID>.log is error messages from the executable, these can sometimes be fatal or not.
crash_ etc is from a crash.
So I guess look at the crash and error files to see whats going on, you might need to reference one of the other logs to get the full picture.