If you want to have several distributions on the same PC, then avoid using the Logical Volume Management at all. It is an excellent technology, but it will be a bit more complicated if you want to access the partition of one distro, when running another distro located on another partition.
Logical Volume Management is meant for a single distro to bind several hard disks and devices to a single volume. With multiple distributions in the game this is not what you want to deal with.
The swap partition can be shared for all distro's, and usually it's safe to have a shared /home on it's own partition as well. But everything else should be separated, as each distro has it's own way of installing tools and configuration files.