It would probably be impossible for a Find/Replace, and even for a macro, to identify with certainty when you do or don't want a particular comma replaced. The Find/Replace works 100% with the sample data you have posted so far. Obviously, though, if you have a sentence like:
First Item: some variable information, but not all
there's no way to know the comma's not one you want to replace.

I don't see how the F/R could possibly insert 'and' at the beginning of a line, unless that line begins with a comma (which would be quite unusual).

__________________
Cheers,
Paul Edstein
[Fmr MS MVP - Word]