Kurt Angle currently holds the TNA World Title, TNA X-Division Title, IWGP Title and TNA Tag Team titles (on his own) hence, he has 5 title belts in total.
The NWA thing is that the TNA titles used to be called the NWA World Title etc, as they were a branch of the NWA and bought the naming rights for a certain period for the titles, this has however finished and they are all known as TNA titles, not NWA.
It should also be noted that the IWGP Title has nothing to do with TNA, but they have obviously come to some agreement so that he can show the title on TV. IWGP is a Japanese promotion that Kurt Angle has done recent events for, hence how he won the title.