Can somebody give me some car advice?

I drive an 07 Yaris [sedan] right now. I bought it brand new & I love it! I love how roomie it is & it gets great gas mileage. The only problem is that I drive almost an hour to work on a good day & if it snows even a little bit or rains really hard, it either takes me hours to get to work or I can't make it at all. Every route to my work involves a lot of huge hills & curves making it nearly impossible to even get out with barely any snow. So, I was thinking of maybe trading my car in [I still have 2 - 3 years left of payments on it] & getting something with 4-wheel drive. I need something good on gas, not too expensive & something that will be very dependable. Any ideas on what I should get?