The answers to your very first post here provided all you need to do the task. I gave you a solution which can be tweaked to not comment lines out, but not print them instead (untested): 
my $comment = 0;
my $block   = 0;

while(<$in>) {
    if (/^zone\s+"$targetdomain"/) {
        $comment++;
        $block += () = /(\{)/g;
        # print $out '// '.$_;
        next;
    }
    if($comment) {
        $block += () = /(\{)/g;
        s!^!// ! if $comment or $block;
        $block -= () = /(\})/g;
        $comment = 0 unless $block;
    }
    print $out $_ unless $comment;
}

[download]

Since that trivial task seems to be too difficult for you, I gave you a link to a tool which handles all things zone file related. Yes, it relies on a database, but if you have to do more than casual changes to zone files, for which you could also fire up your editor and do changes by hand, it is the right way to go.

--shmem 

_($_=" "x(1<<5)."?\n".q·/)Oo.  G°\        /
                              /\_¯/(q    /
----------------------------  \__(m.====·.(_("always off the crowd"))."·
");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}

In reply to Re^3: Deleting lines from named.conf file by shmem
in thread Deleting lines from named.conf file by firewall00

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