Jul 9, 2015 - 4:31 PM
Yes, you can do them in one day if you don't want to do all activities on and around the mountains. It will be a full day but it's doable. Please see the Mount Titlis and Mount Rigi page for tips.
1. I would go to the Titlis first because the risk of clouds in the afternoon is a bit bigger there, plus trains on Mount Rigi run until later. Of course your choice also depends on the weather of the day.
2. Please see the pages I linked to.
3. Well, earlier is better. If you leave around 7 AM you can take the first cable car up. This is an estimate, please see the timetable for details, and enter Kleintitlis as your destination.