If you are looking to change the format, please look at the recommendations here:
http://stackoverflow.com/questions/746972/how-do-you-manage-configuration-files-in-perl
If you're looking to parse the existing format, that format looks to be more of a comma-separated file than a "configuration" file, so I'd say go with Text::CSV (it allows you to choose a separator character in a constructor, so you can do colon-separated instead of comma-separated), or for very large files Text::CSV_XS.
use Text::CSV; # Example adapted from POD
my @rows;
my $csv = Text::CSV->new ( { sep_char => ":" } )
or die "Cannot use CSV: ".Text::CSV->error_diag ();
open my $fh, "<:encoding(utf8)", "test.conf" or die "test.conf: $!";
while ( my $row = $csv->getline( $fh ) ) {
push @rows, $row; # $row is arrayref containing your fields
}
$csv->eof or $csv->error_diag();
close $fh;