Consider a lookup table instead of nested if-else blocks: 
my %lookup = (
   1 => {
      90 => 'Win ME',
      10 => 'Win 98',
   },
   2 => {
      3 => 'Win NT 3.51',
      4 => 'Win NT 4.0',
      5 => {
         0 => 'Win 2k',
         1 => 'Win XP',
      },
   },
);

my $os = $lookup{$id}->{$minor};
$os    = $os->{$major} if $minor == 5;
$os  ||= 'Unknown Win32s flavor';

print "$os, $major.$minor\n";

[download]
UPDATE
Wow - demerphq showed me Determine Windows Type or Version. Just goes to show that both Mr. Muskrat and myself should have done a little searching first. ;)

demerphq++

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

In reply to (jeffa) Re: Which flavor of Win32? by jeffa
in thread Which flavor of Win32? by Mr. Muskrat

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