Convert $vlength to seconds (easy), and use grep in its scalar context:

sub btween (\%$$)
  {
    my ($hash, $from, $until) = @_;

    return scalar(grep { $hash->{$_}->{VLENGTH} >= $from &&
                         $hash->{$_}->{VLENGTH} < $until }
                  keys(%{$hash}));
  }

print "There are ", btween(%hash, 0, 60), " clips between 0-1 minutes\
+n";
[download]

(And so on and so forth)

Update: Oops, forgot the titles. Grep again:

sub btween (\%$$)
  {
    my ($hash, $from, $until) = @_;

    my @found = grep { $hash->{$_}->{VLENGTH} >= $from &&
                       $hash->{$_}->{VLENGTH} < $until }
                  keys(%{$hash}));
    my $titles = join(', ', map { $hash->{$_}->{TITLE} } @found);
    return ($#found, $titles);
  }

my @result = btween(%hash, 0, 60);
print "There are $result[0] clips between 0-1 minutes, and their names
+ are: $result[1]\n";
[download]

Update the second: Rewrote the update in the form of the original sub statement. This doesn't work for 'there are n clips >5 minutes long'-type things. Change the conditional in the grep statement to fix this.

Andrew.