DrBravesgirl, I took a year off before starting. My school was very supportive of that (ask 'em first). I had no problems getting back into the swing of studying. It made me a lot LESS stressed than people who went straight in, even though I did the same amount of work, and I could breathe easier than the kids who went straight in.
Why....
Because I worked-- left at 8:30 and came back at 5:30 every day, and when I left the office I put the work behind me and didn't think about it anymore. The med school day does not end at 5:30 because you have to go home and read the books for a few hours-- but I know that at 10pm or 11:30pm or whenever I get tired, I close the books and the work day is over.
I find that some students who don't have the experience of working "in the real world" do not know when or how to stop during the first semester, and I can sometimes see that they physically study themselves into the ground. They get ill, break out with zits and cold sores, get crabby during the day, and so on. The funny thing is that, with all of that self-torture, their grades aren't necessarily any better. So I think that taking a year off, especially after 3 1/2 years of really struggling in college (I did too) is a great idea.
And I didn't have a fun year off either-- the economy collapsed and I spent more than 6 months looking for a job. That was fairly depressing-- but even that experience made me so much better equipped to approach grad school in a healthy (and happy) way.