to start server:
with craftbukkit- java -Xmx1024M -Xmx1024M -jar [craft bukket vertion]
without craftbukket- java -Xmx1024M -Xmx1024M -jar minecraft_server.jar

reseting nether:
move world_nether/DIM-1 to world/DIM-1

nessisary files: (if not found they will be made)
-banned-ips.txt
-banned-players.txt
-ops.txt
-white-list.txt
-