LocationRadius: Honestly not sure. It is used by several commands I haven't actually used, myself, (/sethome and /tpsave)
TeleportNearDefaultDistance: distance the admin will teleport from player when using /tpn PLAYER. This can be used instead of /tp Player, usually only by admins.
AllowCraft: For each of home, town, and tpr commands, decides whether or not a player can be crafting while using those commands.
CheckValidOnList: Not sure, used only by /listhomes.
BlockedItems: Blocks use of teleport commands while carrying items listed here. For example, if you want to block teleports for some player carrying an M249, you could add that here. I have also never used this.