Error's with Installation

Hello,
About a month ago I got my Windows Vista Beta2 CD key, but recently deiced
to download it seeing as the download would not be available anymore as of
today. I downloaded the large file, burned it as an ISO, and stuck it in my
computer. The install window came up, and I began the install. I did the
quick update, entered my CD key, and then it asked me to stick the CD in the
drive... I said, retry, but the same message came up. I clicked continue,
and everything continued on OK. I came up to the compatibility check part,
and during the check it asked for my CD again. I clicked continue. I got to
the part where it copies the files for installation. It got to 62% then gave
me this error: An error occurred while copying Setup files onto your local
machine. Error code is [80070241].

What should I do now? Should I burn another disk (I hated that part!)? Is
the ISO file corrupt? (haha I hope not, I can’t download it now). Any ideas
would be appreciated!