Downloads listed here are for officially verified releases. If you're not sure which you need, you probably need the 32-bit version 3.x ISO. Alternate ISOs, including daily snapshots, are available here.
N.B. - Always compare the MD5 checksum for an ISO after you download it and before using it to make a bootable media, etc.
|3.2.1 64-bit||bccd-3.2.1.amd64.iso||628 MB||March 2, 2013||(md5)|
|3.2.1 32-bit||bccd-3.2.1.i386.iso||664 MB||March 2, 2013||(md5)|
You may also want to download the build_bootable_usb.sh script for making bootable USB under Linux.
Note: BCCD version 2 is unsupported and not under active development; use at your own risk.