CentOS 4 Offers Strong RHEL Alternative - page 2
The best way bar none to get CentOS is via its well-seeded Torrent. I've kept my BitTorrent client (mostly) available for the last month and have been amazed with how both the number of seeds and peers has remained relatively high and constant.
One of the first issues that many CentOS downloaders experienced (myself included) was problems related to getting their burned ISO to pass the CentOS media check (part of the installation process) even though the MD5 checksums matched up. The well-trafficked CentOS mailing list, as well as its discussion forum, was full of posts on the subject.
The problem had to do with how some Windows based CD burning applications (Nero in particular) didn't (for a long list of reasons that the discussions debate at nauseum) burn the ISO in such a way so they could pass the media check, even though MD5 sums from the ISO download were correct. A number of solutions were offered included a possible fix for the ISO's themselves that the CentOS development team could execute; however no such fix (as far as I know) was ever made. As it turns out Fedora had a similar issue at one point with one of its Test releases, that Red Hat was able to fix in their ISOs.
The solution for most is to (a) burn the ISO's on Linux of (b) Don't use Nero on Windows to burn the ISO's (try a non-buffering CD-burning app instead).