chhoti si Help

[Rehman shar]

yar mene windows 7 ISO file ko USB men galti se burn to kar liya or phir USB ko formate b kia wo is liye k jab main burn kar raha tha to intihai slow speed se burning ho tha or is doran light b chali gai jis ki waja se window sahi tarah se burn nai hui to is liye mene USB ko formate kar diya lekin ab masla ye aa raha hai k main jab b computer ko start karne se pehle Us USB ko connect karta hon to Computer start nai hota,, means har bar >F9/BootFrom/Hardisk karna parta hai tab ja k PC on hota hai Otherwise bar bar Ctrl+Alt+Del means (restart mangta hai)
bus ap dost mujhe ye bata den k main apni USB ko is Formet se kese khatam karon k mera PC USB ko boot na kare???