~snip~
Ledger Nano S is working on Windows 7 with Electrum as user interface, there is no doubt about that. In my case, Ledger Live is stopped working on W7 when I upgrade firmware to 1.5.5, but some other users report that they still manage to use Ledger Live on W7.
So if you only use Bitcoin, a combination of Nano S+Electrum is everything you need, and it will work on Windows 7. It is advisable to make a firmware update to latest version which is now 1.6.0 for Nano S, but it will work even with 1.4.2 or 1.5.5.
I think things are pretty simple, no need to complicate them without a reason.