you can use ext4 for all distro.

Using a single 2Gb swap partition and then one ext4 partion for each distro will do with most of them (not for long term use, as you would prefer separate /home partitions probably). Most of the distro that won't accept that will work with one ext3 partition instead. For the rest, an ext2 /boot and an ext3/4 root should do, but I don't expect you to need that.