All Christians are Catholic, because Catholic means universal. However, not all Christians are Roman Catholic. Person, you have done good by bringing this discussion in the Christians forum, so that the non-believers cannot see and say we are fighting.
But the reasons Protestants do not accept the "Catholic Bible" is because it contains certain books which do not have apostolic authority. Other than those added books and a few misinterpretations, there is no problem. Many Protestants view Catholics(the common definition) as "God father followers." For example, if you ever saw the "God Father" movie, they were Catholics and went to church and the babies in their families were bapized by sprinkling. And despite all that, all the violents acts meant nothing because they were supposedly saved anyway. Then there are these people who wear crosses and kiss it and make the cross sign for "good luck" despite the fact they do not follow the Lord in anyway. But, I know there are some Catholics who are not like those examples and truly follow the Lord and are saved.