my $output = "<!-- 1st table -->What I want 1<!-- /1st table -->more stuff...<!-- 2st movie -->What I want 2<!-- /2st movie -->...more stuff...<!-- 3st movie -->What I want 3<!-- /3st movie -->...more stuff";

if ($output =~ /<!-- 1st table -->(.*?)<!-- \/1st table -->/g) {
	print  $1;
}
else{
	print "Nothing Here!";
}