tamina,
The Itinerary suggested by Sam is along the same lines as what I'd suggest. Start in Stresa (Italy) to get over jet lag and then visit the Lauterbrunnen Valley and Lucerne. I'd suggest staying in Lauterbrunnen during your time there as it's the transportation hub and central to both sides of the valley. You could also stay in Mürren which also has fantastic views, and that's closer to the famous Schilthorn (should you want to visit there). While in Lucerne, you could take a cruise on the lake, visit Mt. Pilatus, etc.
One important point to mention.... Switzerland is expensive so be sure to budget accordingly.
I also agree with the previous comments about Zürich. It's a beautiful city but enjoying the scenery in the Berner Oberland is a better choice.
You can find hotel and sightseeing information for all the places mentioned above in the Rick Steves Italy or Switzerland guidebooks. Check your local Library or larger bookstores.