i have driven between Long Island and seattle at least once a year for the past several years. I believe I pay somewhere around 6 in tolls through Ohio and only a couple i Indiana. (you would think i would have this info memerized) Anyway if you set aside 25$ you should be fine.

Bob may have been right about no trees through most of the midwest and western states but not when it comes to Seattle. It is called the Emerald city for a reason. I personally find the people in Boston to be friendlier (and I grew up in WA state much of that time in seattle). Seattle is more laid back and outdoorsy. I have run with some very diverse crowds in boston from artsy to business to collegiate and i find them overall to be more intellectual. (not necessarily smarter just better spoken maybe is a better way to put it)
Contrary to popular belief it doesnt always rain in seattle. they actually get less annual rainfall than new york. they just have more frequent short bursts of rain as the clouds dump before passing over the cascades.

The drive can be monotonous but you will go through just about every type of landscape america has to offer. My personal favorite is the badlands at sunset. Indiana is annoying but takes only about 1 1/2 hours to get through. south Dakota can be boring if you arent into stopping at any or all of the little touristy spots like Wall Drug, the Dances with wolves place. of cours Mt. Rushmore is a must. Central Washington in the worst. Most people dont realize it is practically desert. I dont know how much of that stuff will be open in the winter so the drive might be more boring than it is in the summer.
Anyway when you arrive in Seattle have fun exploring. Take time for a 3-4 day weekend trip down the oregon coast into california and the redwoods.(farther if you can take the time)go into Canada, vancouver is one of the most beautiful places. you can take the ferry from seattle. explore all the national forests in the pacific northwest. explore all of western canada. You will experience people and places so different from the east coast it is like two different countries some times.(not counting canada in that statement)Have fun and be safe. good luck.