To answer your question: "are these all the same thing..?" No, but there is some overlap between the various ski styles which makes it confusing for newcomers. I'll give it my best crack.
The skiing possibilities in Switzerland are endless, and one can do a number of different styles of skiing without having to go far. What you need to figure out before buying is just what kind of skiing you want to do.
Here's the most common skiing categories you should be savvy with:
nordic skiing (which takes place on groomed skiing trails) is broken down into:
a) classic cross-country skiing (where the skis follow parellel grooves set by a snow grooming machine. Not super strenuous for a moderately fit person. Skis have scales on the bottom to assist in giving you some grip as you shuffle along. Not meant for going up or down steep continuous hills.
b) skate skiing (called "langlaufen" here), is much more strenuous. This is the type of skiing where the skier looks as though he/she is skating side-to-side, as on an ice rink. The skis have no scales (important difference from classic) and rely solely on the skating motion for propulsion, even uphill. Biathalon athletes do this in the olympics. No comparing it with classic! It's much more strenuous. You can go up steeper hills than classic, but you have to be FIT! Also possible to pick up speed going downhill on the groomed trail (because you don't have scales), though you won't be able to stop as easily as you could with normal downhill skiing gear. The boots are soft and the bindings are weak.
Both of the above have bindings that are only connected to the boot via a small connection point at the front of the boot. This is necessary to facilitate traveling forward (because of course, you're not in a lift-serve ski area).
Then there is backcountry skiing (takes place outside of groomed, maintained ski areas), and is sub categorized into:
a) light weight backcountry touring (essentially a beefed up version of the nordic classic touring kit). This setup is meant to give you enough floatation to stay on top of a little fresh fallen snow (ie. wider skis), the boot is warmer, perhaps a bit more weather proof, but the rig is not meant to give you tons of support for making powerful downhill turns at speed. It's lightweight and meant for touring mostly flat terrain or perhaps rolling gentle hills-off trail. You may add a climbing skin (attached to the bottom of the ski to provide uphill grip) for tackling hills on this rig. That will depend on the terrain.
b) telemark skiing -a stylish throwback to the first means of traveling through the hills of Northern Europe on skis. A special style of binding and boot allows both touring (the binding hinges at the toe) and powerful downhill turns by means of a tricky "telemark turn." This is considered one of the harder skiing techniques. It can be frustrating to learn, but is beautiful once mastered. (I liken it to flyfishing). Climbing skins can be affixed for touring uphill. A skilled skier can travel up and down steep terrain in a variety of conditions from hardpacked snow to deep powder.
c) Alpine Touring relies on the same downhill techiques used for normal in-bounds lift-serve skiing, but allows the skier to tour into the backcountry by means of affixing climbing skins, just as in telemark touring. Again, skilled skiers can travel up and down steep terrain in a variety of conditions.
Telemark Touring and Alpine Touring are both going to take you into terrain which will generally require some mountaineering experience. These are not hobbies which you can pick up overnight, as there are real objective hazards involved--namely, avalanches. Most folks who tour into the backcountry frequently will own avalanche trancievers, probing poles, rescue shovels, and will hopefully have the necesary training to use these tools. A knowledge of the science of snow also adds to your safety. It is also wise to have some first aid experience and a couple experienced companions. There are courses you can take to acquire these skills, and also organized tours that you can take part in. The SAC (Swiss Alpine Club) offers a variety.
If you're interested, I put together a 7 minute movie from a 3 day ski tour in British Columbia which I made a few years ago with some friends.
It's on my blog (movie is titled "Resurecting adventures past") here's the link: http://lifeinch.blogspot.com/
I'm the guy on the guy on the telemark rig. The turns will look unimpressive, but hey it was loads of fun!
Hope some of that makes sense. I would definately go to an established ski shop and ask for the full run down before plunking down on a kit. Good luck and have fun with it!