The majority of the Old Testament was originally written in Hebrew (which I can't read), and the New Testament in Koine Greek (which I can read). A few parts of the later OT books were Greek (eg the book of Daniel).
Reading the original certainly gives you a different slant on it to reading translations. One very simple example: the word "angelos" is the ordinary everyday Greek word for "messenger" and the NT very often uses it in that everyday sense. Many translations mistranslate some uses as the word as the English derivation "angel" which has all sorts of "overhead meanings" of supernatural beings who sit around on clouds playing harps associated with it. It sometimes does indeed refer to a "messenger from God" but it's clear from the context that in most cases the "beings" involved were perfectly normal looking people. Goodness knows where the wings and harps stuff came from
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