Update: I missed the Excel/Access requirement, but I can't test that, so I don't even know if this will work or not. It's meant for CSV./Update

Here's a quick attempt that isn't really efficient (it has to read the file twice, first to get the max widths, then to write it out), but it does do what you want (from what I can tell). It puts your first requirement (the padded entries) into a file called out.1, and the output for your second requirement in out.2.

use warnings;
use strict;

use Text::CSV;

my $csv = Text::CSV->new;

my $file = 'in.csv';
my $out1 = 'out.1';
my $out2 = 'out.2';

open my $fh, '<', $file
  or die "can't open the damned csv file!: $!";

my %widths;

while (my $row = $csv->getline($fh)){
    for (0..$#$row){
        my $length = length $row->[$_];
        if (! $widths{$_} || $length > $widths{$_}){
            $widths{$_} = $length;
        }
    }
}

seek $fh, 0, 0;

open my $wfh_1, '>', $out1
  or die "can't open the bloody output file $out1!: $!";

open my $wfh_2, '>', $out2
  or die "can't open the dirty output file $out2!: $!";

my @header;
my $got_header;

while (my $row = $csv->getline($fh)){

    @header = @$row if ! $got_header;
    $got_header = 1;

    for (0..$#$row){
        if (@header){
            print $wfh_2 "$header[$_] : $row->[$_]\n";
        }

        my $elem_len = $widths{$_} - length($row->[$_]);
        $row->[$_] .= ' ' x $elem_len;
    }

    print $wfh_1 join(' ', @$row);
    print $wfh_1 "\n";
}

close $fh;
close $out1;
close $out2;
[download]

-stevieb