<<"The trip is in the second week of May and we only have perhaps three days. We fly in and out of Zurich. Any suggestions for the best use of our visit considering we really will only have 3 days? We would like to see some beautiful scenery and get in at least one nice hike.">>
So would I! By that time of year, I really want to get up in the mountains.
The problem is that the snow has not gone away at the levels of the best Alpine hikes. If you were coming 3 weeks later, you'd do a lot better.
All of Switzerland is covered by a signed trail network called die Wanderwegen. Topo maps keyed to these routes are available at all sorts of places - bookstores, convenience stores (Aperto, Kiosk, Volg) with mostly local maps. So, you can hike at low altitude in May, where the sun is.
www.swisstopo.admin.ch /internet/swisstopo/en /home.html
Each of us has our favorites, and Arn0 and Annika keep a closer eye on the trails and rail passes than I do.
My favorite is Wengen for what you are doing. One of the reasons it is easy to recommend is that another forum member has written extensively about the Jungfrau region, with a focus on Wengen. You have enough time to look it over. ;-)
The best easy hike for a first timer, in my opinion, is described I that report and here:
It's easy, but unless you have a very hot late winter/spring, the trail will not be open. It is at about 2300 meters. Lower trails at maybe 2000, almost surely 1500 meters will probably be open.
That time is in between seasons, and rooms are easy to get, if the hotel happens to be open.
The best way to take that hike is to ride the gondola car lift from Wengen to Männlichen. It opens on approximately June 1. Sometimes earlier. Don't count on it. There is lots of other stuff to do in the area, and you are about 2 1/2 hours from Zürich by train.
Assuming sunny weather - not a given, by the way - there is a lot to do at lower altitude and up to the Jungfrau.
How serious are you about hiking? Technical Climbing? Scrambling?....both not so good until late June or July.
Here is a trail that is at lower altitude on the sunny south facing slope of the Alps leading down to the Rhone Valley.
The description is underwhelming. The hike has a terrific variety of things to see, is almost always in the sun , overall only has a modest altitude loss, although there are a few ups and downs to keep you working. And, a beer garden halfway.
Walk from Hohtenn to Ausserberg, part of the longer hike alongside (more or less) that rail line is a nominal 3 hour hike, but always takes us 5 hours because of phot0graphy and chatting over a beer with other hikers at the beer garden
You take a particular train from Bern or Spiez (The Lötschberger) toward Brig. Plug Hohtenn into the "via" option to stay on the old route or you'll go through a long log new fast tunnel below, instead over most of the route in the mountain air. Stay in Bern or Interlaken or Spiez , ride to Hohtenn, get off, walk a few hours to Ausserberg, ride back to your starting point.
I always use this trail for early season walks.
Here are a couple of useful sites:
The time table has a lot of detail buried in it. once you've picked a patricular route, you can get a route map, among other items.
The link I have given for the SBB takes you to a page where you can enter a "via." Some other links don't have that until you are actually in the timetable.