Yorkie,
This guy may be completely genuine, possibly he has even posted before under a different name, and lots of people use different e-mails to avoid spam...
If he is new to MN, perhaps you could suggest he spends some more time building up relationships with other MNers on the boards, post about his situation, introduce himself etc., and then if you wanted to meet up, I would suggest definitely meeting up with other mums or DHs in tow.
However, the fact that you say his e-mails are strange, and the fact that the only posts on MN with this username were three within a few minutes of each other last week, with no intro, no profile, no first foray posts into any parenting topics etc. raises eyebrows to say the least.
If I were you I would certainly not meet up without a lot more information being shared and without others present. There appears to be enough MNers in / around Wakefield to enable a secure meet.