I think most would say to just walk from HOJO. I hear it's not a bad walk and people on these boards seem to think it wouldn't make sense to drive or take the ART from there.
It doesn't look like the Holiday Inn is within walking distance (it's over on Manchester, right?), so you'd probably need to drive or check on shuttles from there, which would add to the expense, but probably only to the tune of $15/day (if you have a car. If you don't have a car, the cost will depend on the size of your party. I've read ART is $3/day per person) - so you'd have to weigh the convenience of walking distance with the extra $$$ to decide what's best for you.
I haven't stayed at either, so the distance measurements are about all I can help with.