Perl is awesome for web programming. But if your experience with Perl, Python, Ruby and PHP is limited, I believe it is short sighted to quickly strike PHP from the list. The web is full of good things written in PHP, and PHP can be very simple for web programming. I suspect you could get more done in Perl once you learned it. I also suspect you would be up and running with a much easier learning curve in PHP.

If it were my choice, I'd be less concerned with whether the language is OO. I'd be far more concerned with the already written Web Applications and Libraries available so I spent time writing content for the web and less time reinventing the wheel.

Do not evaluate Perl without going and taking a serious look at all the free modules on CPAN.org for Perl

I would be making stuff up if I evaluated Python or Ruby.