Well, I'll step up and recommend the general corpus of Bart Ehrman. His introduction to the New Testament is the go-to textbook for undergrad intro classes (and is on the AH booklist). But in addition to his actual scholarship (he is at UNC), he's published a variety of eminently readable books on Jesus, the Bible, and early Christianity.

My interest runs more towards the biblical and early Church end of things, so my favorites are Misquoting Jesus and Lost Christianities. Here's his Goodreads page so you can click through the different books he's written and see what interests you!

There is no best popular book on Jesus of Nazareth. Every book on Christ, especially those for a general audience, is shaped by an agenda and a targeted audience. Every one.

Bart Ehrman's early books were sound, and much of his scholarship still is, but in the past decade his works have tended towards portrayals of the development of scripture that are vaguely paranoid, as if the history of Christian doctrine is a grand conspiracy to hide the truth. I cite titles such as "Lost Christianities", "Lost Scriptures", "Misquoting Jesus", Forged", and "Jesus, Interupted". He has interesting theories on the development of scripture, but he treats them as the revelation of grand truths against centuries of suppression, as opposed to anecdotes regarding forms of Christianity that died out for one reason or another. This goes for Pagels as well.

Paula Fredriksen has written two books looking at the Jewish background of Christianity, "From Jesus to Christ" and "Jesus of Nazareth" that emphasize (and perhaps over-emphasize) the impact of 2nd Temple Judaism on the early Christian movement.

E.P. Sanders 1996 book "The Historical Figure of Jesus of Nazareth" serves as an introduction to the late 20th-century/early 21st century 'quest for the historical Jesus', which is the probably futile task of separating the authentic teachings of Jesus from later 'supplementary materials' put in the gospels for one reason or another. See also: the Jesus Seminar.

Best bet: one of the most fair and least-polemic works on the subject (and thus not as hyped) is Michael White's "From Jesus to Christianity", which is a fair portrayal of what historians know and what they don't know that doesn't go in for grand theories, just a solid review of the scholarship.

Follow up question: what is the consensus, or lack thereof about Crossan's _the Birth of Christianity. I found it accessible, if dense, but lack the knowledge of the era to judge its content. (I did note that Crossan's shorter, more popular works, lack the substance of this one).