Question in the title. I'm re-playing and Never knew what the order was to play then through as they have a linking story.
Im sure this has been posted before, but I'm not going to sift through all the threads.

Thanks for the help

Dead money>Honest hearts>Old world blues>Lonesome road.

EDIT- whoops, stupid mistake (I put old war blues...lack of sleep is no good)

Thanks a bunch.

I had a similar experience. I downloaded the dlc's in both Fallout 3 and Fallout NV in reverse order and I played them in that order. I knew that and it didn't bother me one bit.

Lonesome Road last and as high level as possible. Honest Hearts is probably the most lower level friendly and could be played first without problems. Dead money shouldn't be played until 20th or so. Think I played Old World Blues around 30th and some parts were difficult but I used mods that rebalanced combat so I don't have a vanilla recommendation.