I, um... drove a good chunk of the 5 hours home from Montreal. I *shouldn't* have, but my wife just wasn't able to handle the whole trip herself and I desperately needed to get home.
After that, I'd say it was 2-3 weeks more (so 3-4 weeks post-op) before I felt like it was both safe and comfortable to drive, but I could manage errands if I really needed to.
The gym, now, took months; I was just so constantly exhausted, and when I was feeling my usual energy levels I still tired easily. I did manage to go for gentle walks and do some light weightlifting, but mostly I needed to rest more than I needed exercise.