Christianity and Catholicism is not different religion. Christianity divided on Catholicism and Orthodoxy. And Orthodox and Catholic, both are Christian.

Christianity is the root of the Catholicism, Orthodoxy, Protestantism, Jeovah witnesses...all followers of Jesus. But they have different interpretations of the Bible.

Just my opinion christianity would be better, as it does not do brainwashing. Though i would be a pagan if i need to choose.

Many people categorize any church that believes in Jesus Christ as "Christian". The biggest difference between the Catholic religion and many Protestant denominations is Catholics believe in Jesus + good works = Heaven. Many (not all) Protestant denominations believe that good works have nothing to do with being justified with God. It is a free gift from God and Ephesians 2:8-9 clearly says that it is not by works that we do. Just like a Christmas gift, you're not expected to pay for it if someone is giving it to you. If they hand you a wrapped gift and say, "Here, this is for you..... now that'll be $20." it wouldn't be a gift.

Cori is qite right. Christianity has 3 main branchs: Catholicism, Orthodoxy and Protestantism. So Catholicism is a version of Christianity.