here is a suggestion how to solve your problem adressing the CGI::FormBuilder issues. you don't need the "variable variables" - use hashes and references instead. (Why it's stupid to `use a variable as a variable name')

#!/usr/bin/perl

use CGI;
use strict;
use warnings;
use CGI::FormBuilder;

# your scripname goes here
my $self="form-test.cgi";

my %hash = (
  video         => "format director producer acter",
  audio         => "album song",
  picture       => "photographer style size",

);

my $cgi_instance=new CGI;
print $cgi_instance->header;

my $approved_todo=$cgi_instance->CGI::param('todo');

if (defined($approved_todo))
{
  #going inside here if $act is defined
  print "you selected ".$approved_todo."<br>";
  #your complete CGI::FormBuilder Code goes here
  my @all = $hash{$approved_todo};

my $form1=CGI::FormBuilder->new(
                                fields=> \@all,

# and so on with your FormBuilder Code

}

else
{
  #go inside here if $act not defined
  print "choose your way of uploading<br>\n";

  my @temp_array=keys %hash;
  foreach my $temp_todo (@temp_array)
  {
    print "<a href=\"".$self."?todo=".$temp_todo."\" act=1>".$temp_tod
+o." upload</a><br>\n";
  }

};

print $cgi_instance->end_html;
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