Hi
Point to Point: is basically configured between 2 routers and no DR or BDR election is applied. Other way to use it is to advertise the real subnet mask of the loopbacks.
Broadcast: it is based in multiaccess, one packet can be provided to multiple destinations through a medium (like a switch), this type requires a DR/BDR election, in few it uses multicast packets. Default type on Ethernet interfaces.
Non broadcast networks: It is used for some situations like using ATM, Frame Relay or DMVPN, There is DR/BDR election here. Basically there is no hardware between them to support broadcast capability. In this type probably the neighbors need to be configured by ourselves.
In NBMA basically all the routers have IP addresses over the same network and they use unicast packets to communicate between them.
Point to Multipoint: There is not DR/BDR election, note with this network type the OSPF hellos are increased in 30 seconds (increased 3 times from the normal time and the holdtime as well). Less cost because it is not a full mesh. OSPF treats the non-broadcast network like a collection of point-to-point links and the neighbors could be discovered automatically.
Also the following link could be useful:
https://supportforums.cisco.com/discussion/9924716/difference-between-nbma-vs-point-multipoint-nb-ospf
:-)
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