[CentOS] 6.2 install disk jumps to Gnome Partition Manager

Have you seen this problem? I downloaded

CentOS-6.2-i386-bin-DVD1.iso

verified the md5sum, wrote on a DVD, verified that against the iso.

When I boot a computer with that disk, It does not present the usual
Linux install menu, it jumps to a thing called Gnome Partition
Manager, and that offers a weird sort of "live disk" interface.

There is no way to start an install, so far as I can see.

-- 

Paul E. Johnson
Professor, Political Science
1541 Lilac Lane, Room 504
University of Kansas