Advice on rail pass for 6 nights Grindelwald

Myself, wife, two children (15 & 11 years) are visiting 3 European countries from 13th May to 30 May. We will be staying 4 nights in Paris, 6 nights in Grindeiwald, 2 nights in Venice and 5 nights in Rome. In Paris & Rome we plan to visit must see places. In Swiss, we plan to visit Mt. Ttlis, Jngfaujoch, Luzern, and other places in Bernese Oberland. Which train pass will be suitable for me. E Rail or Swiss rail pass? Can this pass be used in local metro & bus in Paris & Rome. Any adive will be helpful. Thanks

Welcome to MySwissAlps, Solomon!

Which pass is best can only be told if you make detailed calculations for all your plans, including those for France and Italy. A three country Eurail Select Pass might work, but only if you plan quite extensive traveling in all three countries. Unfortunately, Eurail Pass coverage for the Jungfrau Region you plan to visit isn't that good. You can check by studying the "Validity" section of the page I just linked to.

In all, a pass just for Switzerland may work better. Apart from that you'd have to find what's best for your visit to Paris and Venice/Rome. For Switzerland, you seem to be visiting several regions, as Lucerne and Titlis aren't in the Bernese Oberland. You'll also have think about your inbound and outbound train trips from France and to Italy. So I'd recommend a pass that's valid throughout the country and not just for one region. You can look into an 8 day Swiss Travel Pass and a Swiss Half Fare Card and see if these might suit your needs.