Heh. Gotta love AD&D auto-dicerollers. 4d6, all 1's are 2's, drop the lowest. *laughs*

There's a much better way of doing what you're doing.

sub roll_die
{
    my ($sides, $min) = @_;

    return int(rand($sides - $min + 1) + $min);
}

sub my_roller
{
    my ($num_dice, $sides, $min_value, $num_to_drop) = @_;
    $num_dice ||= 3;
    $min_value ||= 1;
    $num_to_drop ||= 0;

    return () unless $num_dice >= 1;
    return () unless $num_dice > $num_to_drop;

    my @values =
        sort { $a <=> $b }
        map { roll_die($sides, $min_value) } 1 .. $num_dice;
 
    return @values[$num_to_drop .. $#values];
}

my @values = my_roller(4, 6, 2, 1);
print "@values\n";
[download]

This code has been tested relatively thoroughly. You should be able to just drop the functions into your existing code, or run it separately as provided.

Improvements made over what you posted:

1. I separated out the thing that actually does the rolling from the thing that does the collating of the values. This is important because you might want to change them separately.
2. I also made a function to do the collating. This is important because you want to roll dice for reasons other than generating stats. For example, you can get a combat roll by my $roll = my_roller(1, 20); In other words, 1d20.

If you want an explanation of how the code works, please ask.

------
We are the carpenters and bricklayers of the Information Age.

The idea is a little like C++ templates, except not quite so brain-meltingly complicated. -- TheDamian, Exegesis 6

Please remember that I'm crufty and crochety. All opinions are purely mine and all code is untested, unless otherwise specified.