I'd like to know which way is better to move inside this country. I heard that car is the best choice due to the lack of public transports that make small towns far from the biggest cities difficult to reach.
Yes that is true. There is actually quite a good train system in Sweden which links most towns but it is bloody expensive though. Busses are quite good but pricey as well. Flying is cheap but its ironically usually cheaper to fly to anywhere else in europe besides sweden. A few of my mates actually pushbiked all the way from Uppsala to Gothenburg, the country is really flat and there are good bike lanes.
Im thinking though that the cheapest way to see the place is with a eurail or interrail ticket, or renting a large car with a heap of mates and splitting the $2odd per liter petrol. over 8 years ago
Train is crazy expensive if you do not book long in advance. Bus is cheaper and takes you almost everywere. For longer journeys i recommend going by air. Sweden is a long country and you can get good deals. Especially between the big cities.
But i agree with the rest. Renting a car is probably the cheapest and you will be able to see more off-the-beaten-track places. Make sure you get free milage when you rent and check out several car rental firms. about 5 years ago