Ignore lines until you see Buffers, then read in another line:

while(<DATA>){
    next unless /^Buffers/;
    my $line = <DATA>;
    print $line;
}
__DATA__
100000
# Event  Snoopy   Snoopy   Replay   Replay   Current  Current
Buffers   ID      Position  ID      Position   ID     Position
1024     1667721  2975e7c  1667717  6d44e10  1667721  2982000
11111
Buffers
Another good buffer line
[download]