A very nice trip is taking the boat from Luzern to Vitznau, train up to Mt. Rigi (the Rigi Kulm stop at the top), then train and cable car back down to Weggis, then boat back to Luzern. An additional bonus is that if you're buying a Swiss Pass, the entire trip is 100% covered (parts of the trip up Mt. Pilatus are only 50% covered).
If you have any difficulty climbing down steep inclines, take the train back to Vitznau instead; it's a 10 minute walk, all VERY downhill, to get from the Weggis cable car stop to the Weggis boat dock. At Vitznau, the train and the dock are close and the path between them is nearly level. Whatever you do, don't take the boat to Weggis from Luzern, unless you want a very steep 20 minute climb to get from the boat dock to the train going up the mountain.
For a hotel, I stayed at the Hotel Des Alpes http://www.desalpes-luzern.ch/en/welcome, and would do so again. I found it in Rick Steves Switzerland. It's in a very convenient location, in the old town but close to the river and the train station. For this hotel, and indeed both of my other hotels in Switzerland, I found that the hotel's own website booking engine did not have the rooms I needed, but I got them easily by emailing the hotels directly.
My favorite meals in Switzerland were at Manora, the restaurant/cafeteria run by Manor, a department store. Everything is cooked fresh. For instance, if you go get fish, it's not sitting pre-cooked under heat lamps; they take a piece of raw fish off the ice and cook it for you right there. It's about half to a third the price of normal restaurant, and delicious (they also run a fancy grocery store in the basement, so that's where the food comes from). The only problems are that it's only open department store hours, which means early dinner on weekdays, no dinner on Saturdays, and no meals at all on Sundays; and it's VERY popular with locals, since it's such a good deal, so it's always mobbed.
