Question about Buddhist meditation?

Yes.
Buddhism does not require NOR forbid god concepts.

Of course! Meditation isn’t just a Buddhist tradition. There’s many different forms of meditation (especially in the hindu tradition) and no restrictions based on faith.
I recommend you watch these videos: http://www.youtube.com/view_play_list?p=603BD0B03E12F5A1

Anybody can! Just breath in, then breath out. And try and smile occationally.
Any ‘mantra’ will do, there just to keep the mind focused.

Yes. There are many forms of meditation, but meditation is of course a PRACTICE and not merely an idea or a belief. A lot of meditation, in fact, is precisely about getting in touch with an humble and honest experience that’s more simple than any thoughts or ideas we make up.
Meditative experience is before words, so you can get persons in different parts of the world who use different religious words but who are actually describing the same kinds of practical spiritual experiences.
As others have already answered, while there are different kinds of Buddhism, most do not require anyone to accept a “creed” — you can do the practices, and benefit by them, without being forced to make special commitments to specific metaphysical notions.
Also, btw, there are Christian sources of meditation that are virtually identical to some of the Buddhist techniques. A classic example is The Cloud of Unknowing (and it’s “sequel,” The Letter of Privy Counsel). A modern example is Thomas Keating’s book, Open Mind, Open Heart (about what he calls “centering prayer”). Still another example, is a book by Ruben Habito — ordained a Jesuit priest and also a practicing Zen Buddhist — called Living Zen, Loving God.
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