As far as i am aware its only the Ultimate DVD that includes 32 and 64 bit versions.

If you buy a 32-bit Home Basic, Home Premium, or Business version and want to install a 64-bit version you have to order an extra DVD directly from M$. The 32-bit packages include instructions and a website link on how to upgrade to 64-bit.

32-bit CD
If your system features a CD drive but no DVD drive, you can order Windows Vista on CD-ROM. The installation files span multiple discs, so unattended installations are not possible.

64-bit DVD
If your system features a 64-bit processor, you can take advantage of its advanced design by ordering 64-bit software media. You'll get the same interface, features, and functions, but you'll get them in an operating system that takes advantage of access to vastly more memory. All installation files are on a single disc. Please note that 64-bit media is included in the box with the purchase of Windows Vista Ultimate.
More info: here and here