External Formatting problems :(

I have a 250gig external hard-drive ive had for about a year or so. anyway it started to act up and not allow me to transfer any files over a gig to or from it. worried that it would break down, i made a back up of all my artwork and everything important on to several disks and decided to format the external. during the format sadly my cat his the cord and disconnected it. Seance then for the last 3 days i have tried twice to format it to ntfs and after HOURS of formatting it just seems to stay at 79%. I even left it over night and it was still at 79% when i woke up the next day. I have been doing it with the disk manager, I'm running windows vista. Am i doing anything wrong? please help me out, i would hate to have to buy a new external HDD. :sigh: :4-dontkno