cant boot any OS

i recently got my hands on a windows 7 ultimate. i was using xp pro and i dont have the install disc for 7 so i had to run dual boot. i used easy bcd to remove windows xp from the boot options but it lagged and i accidentally removed both xp and win7 from boot options and now i cant get into any OS at all. the only way i thought of that i could get back into windows xp so i could re-install win7 was eaither using the recovery console by booting off of my windows xp disc or by totally reinstalling windows xp and installing win7 again but i was trying to avoid doing the second option since its most time consuming of the 2 options. i'd really like to do a clean install of win7 so i dont have to fool around with xp at all but since i dont have the win7 disc annd the setup file is not an iso image i'm not sure if that is possible. i know that i can use and external drive to do the install but i really have no clue how to do that either. i know it would require making my external drive bootable but i dont know how to do that. anyone have any ideas how to fix this problem?? i'd really hate to have to take another 3 or more hours doing this the way i already know so any help would be greatly appreciated.