Of course, you'll be using CGI.pm for this task...

#!/usr/bin/perl -w
use strict;

use CGI qw(:standard);

open(FILE, '/path/to/file') or die "$!\n";
my @text = <FILE>;
chomp @text;

print header,
      start_html,
      start_form(-action=>'/cgi-bin/myscript.pl'),
      scrolling_list(-name=>'list',
                     -values=>\@text,
                     -size=>5),
      submit,
      end_html;
[download]

You might need to add a bit more HTML :)

--
<http://www.dave.org.uk>

"Perl makes the fun jobs fun
and the boring jobs bearable" - me