Hi,
If my thinking is correct (and it may not be, but I'm pretty sure it is), the eastern side of BU is on the green line (B-line) and Davis Square is on the red line. This would mean that in order to get from your home to BU, you would have to go all the way to the Park Street station via the red line, switch to the Green B-line there, then take that all the way back to BU. That might be a pain. Find out what stops those locations correspond to and then go to http://mbta.com/ to plan your route. There may also be a bus route I'm unaware of (the green and red lines I just mentioned are train lines.) Honestly, I would recommend finding an apartment that is on the B-line. How long do you want your commute to be? Don't resolve to a long commute with the justification that you will do work on the subway: it is often so crowded that you won't be able to find a seat, let alone do work.
As for driving: I'm from Boston originally, so I am really opposed to the idea of needing a car to get around. I would not recommend relying on a car to anyone, especially in Boston. I'm told parking is a real pain to find and is very expensive, so that's something to consider.
Sorry if that was really confusing. Please PM me or respond here if you need clarification on something, and feel free to post anything I wrote in a Boston related SLP thread.