Train to Paris

Let the computer do the work. If you use the Swiss railways site sbb.ch/en, it will show you the fastest train routes automatically.

Fastest and simplest is through Basel with only 2 changes at Interlaken Ost & Basel. Geneva has more changes and takes longer.

When analyzing routes on SBB you should always take into consideration time AND changes. For example, on a long train route moving from one country to another, I’d rather spend 30 minutes extra getting somewhere if it saves me 2 train changes. Every time you get on/off a train it adds complexity, possibility of error, logistics of luggage, etc. In your case, Basel is both quicker and simpler, so it’s a no brainer.

You could also go via Montreux to Lausaunne where you get the TGV.

But that would not be the fastest. Through Basel is the fastest.