Both Spanish and Basque (Español and Euskera) are official languages in Navarra. Spanish is more spread than Basque in Navarra, and everybody can speak Spanish in this land, but Basque is also spoken by a wide part of the population specially in the north of Navarra and Pamplona as a native language.
Pamplona has quite good railway system, although high speed trains won't be working until 2012, it has several trains every day to Madrid (3h), Barcelona (4h), Zaragoza (2h) and so on.
Navarra is called "Land of diversity". From Pamplona, in 50 miles around, you can enjoy forests (as Irati Forest), caves (Mendukilo, Zugarramurdi, Urdax, ...), Pyrenees Mountains, River Springs (as Urederra river), Castles (Javier, Olite, ...), Monasteries (Leire, Urdax, Oliva,...), desertic landscapes (Bardenas Reales), Natural Areas (Urbasa, Arbayun and Lumbier Gorges...), ...
Anyway, most of tourist who arrive to Navarra do it for two main reasons: St James Way (El camino de Santiago), and the running of the bulls festival in July (San Fermín).
To visit and enjoy so many interesting places, the best option is to rent a car, because public transportation is not so available, with few services and usually don´t arrive to the best places (as Irati Forest or Bardenas Reales).
Also, if not speaking Spanish is a bit complicated in some areas, as only in a few tourist attractions English guides are available (as I remember only at Olite Castle and Roncesvalles with audioguides).
Another easy option to visit this areas without worrying about renting a car or language problems it's to do a tour with some local tour agency.
Navarra has a very good reputation for its food and restaurants sharing it mostly with the Basque cook. These are some of the most typical products of Navarre:
Sparragus eaten with mayonaise.
Alcachofas vegetable typical from Tudela.
Piquillo peppers in the village of Lodosa, really tasty!
Txistorra/Chistorra is a kind of red sausage(made with pork meat), delicious.
Patxaran is the most typical alcoholic drink of Navarra. It's destilled with blackthrons and it has an intense red colour. It has 30º approximately.
Wines are also very famous in this region producing wines with Rioja label, and also with their own certification label (D.O. Navarra).