Switzerland is very unusual because it has four official languages: German (the most used, in 2/3 the country), French, Italian, and Romansch. Expect those languages spoken mostly near the borders of those countries and Switzerland, except Romansch, an isolated language used in Graubunden (Grisons) in eastern Switzerland (southeastern Swiss canton, close to Italy and Austria). Romansh is a descendant of the spoken Latin language of the Roman Empire, which replaced the Celtic and Raetic languages previously spoken in the area by the 5th century AD.
Highways go in through twisting mountain passes, from those countries as well.
Rail is probably the best way to get around. With the awesome scenery, you'll probably rather concentrate on it rather than driving, but driving will work fine too, but prepare for some steep roads and tight curves in some areas. Road conditions are, however, excellent and signposting of potential dangerous road stretches are common. Be aware that in winter manz mountain passes close and roads can be icy and partially covered in snow.