Nov 11, 2015 - 9:33 AM
Thanks for the additional details. I would recommend to change your places to stay. Wilderswil is fine for a Jungfraujoch visit, but the others are pretty far away from the attractions.
Saas Grund to Täsch takes at least an hour. Then you have to park, take the train to Zermatt, and another train to Gornergrat.
Lausanne is very far from Rigi Kulm. It will take 2.5 to 3 hours to reach the base station in Arth-Goldau. From there you can take the cogwheel train up the mountain (for example).
Personally I would pick one base town, park the van, and take the excellent trains to reach the attractions. It's quite tiresome to visit Jungfraujoch and afterwards do the long drive to Saas-Grund, including a car train. Likewise, driving from Lausanne to the Rigi, going up, and then drive to Germany is quite a lot for one day too. Changing hotels takes time, and moving around makes you less flexible: the weather has to be good enough to go up the mountain on the single day you have available. With one base it's easier to adapt to regional weather.
If you want to move from town to town, I'd recommend to stay near Lucerne first (Rigi), then move to Wilderswil (Jungfraujoch), and finally Täsch (Gornergrat). You don't need the van for the day trips. In this case I'd recommend the Swiss Half Fare Card (click Price to see purchase option).
In case of one base, I'd recommend the Swiss Travel Pass. From Spiez or Thun, for example, you can easily reach Jungfraujoch, and there are quick InterCity trains to Visp, where you change for Zermatt. Rigi is farther away, but doable, and there are two scenic train lines to choose from.
I hope this was useful!