Provocative though that might be as “spam bait, and nothing more,” the key take-away that I glean from the original post is that “the OP does not yet know what s/he wants to achieve, let alone how to achieve it.”   And, until that point is reached, quibblings about “CGI vs. FastCGI vs. mod_perl” are entirely beside the point.   This seems to me to be “a very basic question, thoroughly clouded by buzzwords.”

Anyone in such a position would find himself/herself equally confused, “equally without a plan,” whether they were working in Perl or PHP.   (Since I count myself equally-conversant in both tools, and many more, I do feel that I am qualified to say that.)   The first order of business now should be to define what (exactly!) is the problem to be solved.   From this, everything else will follow.   At this point, we should assume that “good ol’ CGI” will be more-than sufficient, given that the OP does not yet appear to be decided as to what to implement, let alone how.

(And this, by the by, comes as absolutely no surprise.   The discovery process is, after all, methodical.   “One step leads to another, and if you try to rush things you fall upon your a*s.”)