there is a guy on youtube that has all his stats and skills maxed out on x box befor HH and if he picks up things his weight stays at zero but he did kill every one and finished it in 30 mins

He's using cheats- it's that simple. The big clue is that his weight stays at 0 even though he's picking stuff up. That shouldn't be happening if he maxxed his stats "leagally".

New Vegas was specifically designed to prevent someone from maxxing out their stats, mostly as a response to people complaining how easy it was to max stats in FO3, especially after Broken Steel (where you would have to work to NOT max most of your stats.)

in 30 MINUTES,... heck talk about rushing the game just for looting, :facepalm: