it just locks up my command prompt (Windows XP).

Your program takes a long time to run because tracert takes a long time to run.

All I want to do is scan an IP and get the machine name back-

tracert has nothing to do with that. You want gethostbyaddr.

use Socket qw( inet_aton AF_INET);

my $addr = '209.197.123.153';

my ($name) = gethostbyaddr(inet_aton($addr), AF_INET)
   or do { die "No name for addr $addr\n" if $!==0;
           die "gethostbyaddr: $!\n";
         };

print("$name\n");  # perlmonks.pair.com
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