Maybe something as simple as this?

#!/usr/local/bin/perl
use strict;

while (<DATA>) {
  if (/Host System [^#]/) {
    print "$_";
  }
}
    
__DATA__
Status Host Pluto up
Host System Pluto 10.1.4.11
Host System Mars IP 10.1.3.10
Status Host Jupiter down
Host System #neptune IP 10.10.10.10
Disk load Mars imminent
Host System Venus IP 12.1.2.13.14
[download]