That there was some sort of belief in re-incarnation in NT times (which is to be found also in later judaism, cf. for instance http://www.kabbalaonline.org/Introductions/firststeps/Judaism_and_Reincarnation.asp) and it was not limited to the coming back of "Elijah" in John is also clear from Mark 8:21ff and parallels:
Jesus went on with his disciples to the villages of Caesarea Philippi; and on the way he asked his disciples, "Who do people say that I am?" And they answered him, "John the Baptist; and others, Elijah; and still others, one of the prophets (Matthew specifically mentions Jeremiah)."
This is interesting in many ways, for it attests a tradition in which Jesus, not John, was Elijah; and another (?) in which Jesus was John the Baptist (the latter flatly contradicts the general Gospel picture that John and Jesus were contemporaries, cf. also the expression "since the days of John the Baptist until now" on the lips of Jesus).
The transfiguration story, which is followed by another identification of Elijah to John (Mark 9//), is also related to this issue, since the vision of three distinct persons (Moses, Elijah, Jesus) ends on the following climax: "they saw no one with them any more, but only Jesus."
As for the meaning of the name Enoch (Hebrew chanok), which appears in two parallel genealogies in Genesis (of Cain, J, 4:17; of Seth, P, 5:18ff), it has been explained in a number of ways: according to the Canaanite chanaku, meaning "follower", "adept"; in Biblical Hebrew it is related to the root chnk which is used in the sense of "dedicate" (cf. the feast of Hanukka), which is also attested in Palmyrene. Or from Egyptian chnkt, referring to the foundation sacrifice (Enoch son of Cain is the founder of the first city). In Hebrew tradition Enoch is a solar symbol (he lives 365 years!), which became very important in the Qumran tradition -- especially in the Book of Jubilees which promotes a solar calendar. Thinking about it, the fact that Hanukka corresponds to the winter solstice, just as Christmas, may be more than a coincidence.