You're talking to Logan but I'm gonna chip in and tell you that it isn't distance that matters, it's time/caloric expendature. That is, assuming you're trying to lose weight instead of actually train for distance running.
I don't think I could exercise for two hours straight, at least not yet.
I exercised yesterday in the morning before work, and then when I got home from work, and then before I went to bed and it was probably around two hours or so total. I plan to do the same today.
Of course it's probably more beneficial to do it all at once than spread out over the day.
ive jog/ran 30 min straight every night for over a week. I usually go more than 2 miles in that time. Although I did run for 40 mins and covered 2.7 miles in one night. Ive lost about 10-15 pounds since a little before christmas