@ongaku
I'd encourage just diving right in and when you hit something you don't know, turn elsewhere to try to understand it (basically, prerequisites on an as-needed basis). (Or post a question here, I'll try to explain if I see it and can help.)
That said, flipping through the amazon previews quickly, it looks like you'll be off to a head start if you have some familiarity with (1) logical proofs and (2) set theory & notation. (How one acquires such understanding is left as an exercise for the reader. ^_^)
Of the two zoo mentioned, the analysis book might be more accessible.. but real analysis was my favorite course, so my perception is probably biased ;).
It opens with this,
Toward the end of his distinguished career, the renowned British mathematician G.H. Hardy eloquently laid out a justification for a life of studying mathematics in A Mathematician's Apology, an essay first published in 1940. At the center of Hardy's defense is the thesis that mathematics is an aesthetic discipline. For Hardy, the applied mathematics of engineers and economists held little charm. "Real mathematics," as he referred to it, "must be justified as art if it can be justified at all."