I actually prepared an openbox + step by step review and will talk about this.

hodler do not need to change anything, you will get your 2X coin when it activates.

Direct reply to your question above:
When you choose Bitcoin, the next screen is Legacy and SegWit. This SegWit is the soft fork of August (that I will be using next time I move my BTC in.) I suppose you just got the new device, and will need to send in your existing coin - use Bitcoin->SegWit. Once you already send in your BTC to Ledger, you should not need to do anything to get the new 2X coin, unless Ledger changed something.

When you start the wallet app, you see Bitcoin and Bitcoin Cash, actually there is a hidden SegWit2X entry there for the new chain

The only thing I am not sure is Bgold for Ledger. I will probably move my btc to Mycelium wallet on 24th Oct and then move back to Ledger Nano S on 27th Oct to make sure I can claim it. (do not do it if you are not sure)

Contact me if you need help ^_^