Here's my stab at #4 and #5.

It uses HTML::TokeParser::Simple as suggested by marto above. If there is HTML in the air I won't leave home without it. :-)

#!/usr/bin/perl

use strict;
use warnings;
use HTML::TokeParser::Simple;

my $file = 'home.html';

my $p = HTML::TokeParser::Simple->new($file);
my $html;

while (my $t = $p->get_token){
  if ($t->is_start_tag){
    my $tag = '<'. uc $t->get_tag;
    my $attr = $t->get_attr;
    my $inline;
    for my $name (keys %{$attr}){
      $inline++, next if $name eq '/';
      my $name_value = sprintf " %s=\"%s\"", uc $name, lc $attr->{$nam
+e};
      $tag .= $name_value;
    }
    $tag .= ' /' if $inline;
    $tag .= '>';
    $html .= $tag;    
  }
  elsif ($t->is_end_tag){
    my $tag = sprintf "</%s>", uc $t->get_tag;
    $html .= $tag;
  }
  else{
    $html .= $t->as_is;
  }
}

print $html;
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