Which Rail Pass

We are a group of 4 adults who will be visiting Switzerland in September 2013. We will be staying in Murren for 3 nights and will have a car so i will not need rail transportation from Zurich to Lauterbrunnen. While we are there 2 of us would like to do the Jungfraujoch as well as the Schilthorn. We may also visit First. We will be spending 1 night in Zermatt and plan to take one of the Excursuions to get views of the Matterhorn. Which rail pass would work best for us remembering we will also need it just to go back and forth to Murren?

Which pass would work best for the other couple who does not want to do Jungfraujoch but would be doing everything else?

Thanks Arno! After researching more myself that was the decision I had come up with too but it sure helps to have someone confirm it. I will definitely take your advice on waiting to see if any good deals come along too. This whole rail system can be a bit confusing when you come from an area that doesn't have rail or subway.