CLS
 BREAK ON
 DIM $container
 DIM $containername
 DIM $computer

 $logfile='H:\MMCInvent1.csv'
IF EXIST($logfile)
   DEL $logfile
ENDIF
for $i=0 to 10
   for $j=1 to 255
      $res=wshping('1.1.$i.$j',1)[0]
      if @error=0
        $data='1.51.$i.$j'
        ?'found '+$data
          LOGGER($logfile,$data+@crlf)
      endif
   next
next

for $j=1 to 255
   $res=wshping('2.2.255.$j',1)[0]
   if @error=0
     $data='2.2.255.$j'
     ?'found '+$data
       LOGGER($logfile,$data+@crlf)
   endif
next


for $i=0 to 16
   for $j=1 to 255
      $res=wshping('3.3.$i.$j',1)[0]
      if @error=0
        $data='3.3.$i.$j'
        ?'found '+$data
          LOGGER($logfile,$data+@crlf)
      endif
   next
next

1. If you *must* ping, use a parallel pinger and parse the results.
   
2. Query your DNS server for your zone(s). This will give you your statically assigned addresses, also those devices that can dynamically update DNS.
   
3. Query your DHCP servers for dynamically assigned addresses - where a MAC address appears more than once only use the most recently assigned address.
   
4. Consider using a program specifically designed to do what you are attempting. I use nmap from http://www.insecure.org/ - it's a *nix tool but they do support a Windows port.