Looking to rent a car in Sweden, any advice?

[Lyrynx]

My grandmother on my mom's side was Swedish, though she was born here in the States. I've always wanted to see where my ancestors actually lived before they came over. Finally decided I'm doing it this year, booked some time off and started planning the whole thing. I'll need a car to drive around and visit those places. How does renting work in Sweden? Are the roads decent? What paperwork do I need to bring?