Xbox Problem Please Help Me

ok so i got an xbox and i put evox on it with mechassault and the game saves and all that and it worked then i tryed to ftp xbox media center over to the xbox and i accidentely delted a lot of stuff off the xbox now when i turn it on it does the little xbox sign and the screen goes blank then i tried slayers auto installer turned it into an iso put it on a memorex cd-rw and put it in and the screen is stil blank wat should i do please help

-dfnewb

 

o yeah and it doesnt boot games