Ok, Im a bit rusty with my theology here...specially catholic.
The Catholic church belives that its is the direct 'descendant' of the church instituted by Christ, he never named this Church mind you, he simply founded it, on Peter, one of his closest Apostles. Peter then went on to become the bishop of Rome. Afterwards the Pope office was instituted (I dont know if thats the term in english, but I dont know if Popecy is correct) that lead to the schism with the Greek Orotdox church and other churchs in the East, still their rituals are valid for us and we can attend their ceremonies with no problem, because the reason of the rupture was more human/political , rather than dgmatic/spiritual ones. I love going to Ortodox temples and their ritual is much more rich and much more full of mysticism.

Catholics belive Protestants are sorta 'stray sheep' that have wodered off the Mother Church...there have been attempts with this Pope to reach a common ground and such. Ecumenical congresses I belive they are called.
Its difficult to pin point a TRUE point of view, many 'official'statements can be made, but some say something and do something else. Many Priests belive paganism is not sinful in essence...thats is untill you recive the word of Christ after which you do become a sinner if you dont embrace it.

Budism,Hinduism and other religions are viewed with 'respect' yet not as way to the Christian God.

Judaism is viewded as "Old school"of sorts and we are basically waiting for the Jewish to belive and convert...although that would mean the End of Days mmmm.

Islam is similar to Judaism and are basically distantly related, although Rome does not have as much relation with them as with others.

So in conclusion (I know I ranted a lot) The Catholic church belives its THE chucrh Jesus left on earth to guide the world...and else is taken it that measure.
"Life has a funny way of trying to make you a certain type"

Will Young

"I eat red meat, drink dark beer and I like to get facials and manicures once in a while."

Link.