I've read both, cover to cover.
The Origin is a worthwhile read for anyone; full of fascinating biology and a powerful introduction to the argument for Evolution. It is, however, somewhat kludgy and turgid by modern standards and outdated in technical detail.
The Bible, on the other hand, contains precious little of interest. Is a depressingly tedious book that borders on the incoherent and of little use in understanding Christianity as their religion - despite what fundies protest - is only tangentially related to anything the Bible says, especially the teachings of Jesus. There's a few gems in there, to be fair, but they're hardly worth digging out.