every one believes that Mohammad (SAWS) was the last prophet. apart from that they believe in imams also. as you mentioned, hasan as imaam not prophet. it is your imagination, you just want to create confusion among muslims. you call yourself a student of religion, but in fact you dont seem to know anything.
the argument is not at all like you are mentioning. dont try to learn islam from wikipedia and your RSS classes. go and read the authentic books. read Quran with meaning and understand it. go and find if shias read any different Quran. if they read the same, one they keep your mouth shut. your conspiracy will never succeed as long as we all read the same Quran, we may get mislead but our Quran will always bring us together.
just see the open letter of Ahmadinejad (a shia) to bush and find if there is any message in that which goes against islam (what you call wahabis religion)....
not only you are a conspirator, rather you are an idiot as well. osama himself never claimed prophethood. you seem to the follower of khabees ahmadia group. who claimed prophethood, now you are trying to create confusion. you know he is the last, then go and make an idol of his and worship like your brothers do. sai baba became new god, moinuddin chishti (RA) in ajmer became new god for so many people but islam still stands intact. prophethood finished with Mohammad (SAWS) himself.