I suggest one of the book I recently bought:
Pavel Pudlak: Logical Foundations of Mathematics and Computational Complexity - A Gentle Introduction; Springer Monographs in Mathematics; 2013
I had not ("still haven't" :-) a strong background on logic and this book is helping me to better understand some "fundamental" aspects of logic and its relation with computation and complexity. Doubtless a good introductory book.
The TOC and preface of the book are downloadable from the Pudlak's home page and you can also find some excerpts of the book on http://books.google.com.
From the Introduction:
... The first two chapters are an introduction to the foundations of mathematics and mathematical logic. The
material is explained very informally and more detailed presentation is deferred to later chapters....
Chapter 3 is devoted to set theory, which is the most important part of the
foundations of mathematics. The two main themes in this chapter are: (1)
higher infinities as a source of powerful axioms, and (2) alternative axioms,
such as the Axiom of Determinacy...
Proofs of impossibility, the topic of Chapter 4, are proofs that certain
tasks are impossible, contrary to the original intuition. Nowadays we tend
to equate impossibility with unprovability and non-computability, which is
a rather narrow view. Therefore, it is worth recalling that the first important impossibility results were obtained in different contexts: geometry and algebra. The most important result presented in this chapter is the Incompleteness Theorem of Kurt Godel...
Proofs of impossibility are, clearly, important in foundations. One field
in which the most basic problems are about proving impossibility is computational complexity theory, the topic of Chapter 5. But there are more
connections between computational complexity and the foundations....
In fact, there is a field of research that studies connections between computational complexity and logic. It is called ‘Proof Complexity’ and it is
presented in Chapter 6. Although we do have indications that complexity
should play a relevant role in the foundations, we do not have any results
proving this connection. ...
Every book about the foundations of mathematics should mention the basic
philosophical approaches to the foundations of mathematics. I also do it
in Chapter 7, but as I am not a philosopher, the main part of the chapter
rather concentrates on mathematical results and problems that are at the
border of mathematics and philosophy ...
It doesn't cover FMT and descriptive complexity, but there are a few good books that are focused on those topics (e.g. Leonid Libkin: Elements of Finite Model Theory; Texts in Theoretical Computer Science. An EATCS Series; 2004 )
I accept my answer because I hadn't the opportunity to read the book suggested by Trung Ta, yet.