Hello all! A friend and I are planning on making the trip from Seattle to Boston beginning a couple days after Christmas. As neither of us has driven a long-distance road trip before, I was hoping to collect from experienced drivers! I have learned a lot from browsing the forums here, but I have a few more specific questions. We would like to see some things, but the trip needs to be relatively brief, cheap, and most importantly safe.

Here are my main questions:
1. We have about 6 days, 7 days maximum to make the trip. Is this feasible and safe? Is 90 the best way to go safety-wise? Are there faster or safer alternatives?
2. We will be driving a Toyota 4Runner with 4WD. Is it necessary to look into winter-tires or chains? We are really looking to minimize cost...
3. Cheap hotels--any advice? We don't have AAA. What is an appropriate budget for 6 nights hotel accomodations?
4. We are both confident drivers, but we are worried (and our families are worried) about the weather. Should we be?

Thanks so much in advance! Any other advice or insight is appreciated, as well!

Lauren