I don't know too much about Catholicism vs Protestantism but I find Catholics to be Christians. They believe in the main doctrines (Trinity, meaning of Christmas, Good Friday, Easter, etc.). They don't pray to the saints, but they ask for the saints to pray for them (if I understand correctly). To me, this seems to be similar if I ask someone else like a friend to pray me (I'm not praying directly to God in this sense, but asking someone else to pray for me). The biggest distinctions are that Protestants believe in faith alone, and scripture alone, whereas Catholics believe in both faith and works, and scripture plus tradition.
Protestantism is only about 500-600 years old, and is fairly new. Personally, I've questioned the credibility of Martin Luther (founder of Protestantism) after I learned that he wanted to remove a few additional books from the New Testament such as Hebrews, James, and Revelation. He had concerns over these books because they supported faith plus works-based salvation. So, sometimes I think we should just rely on the original (Catholic) Bible that has all the books.
A big reason due to the different beliefs is that we are using different books.