First Time Player - Recommendations on Order

Hey all,

Friend of mine is a huge Fallout fan, pushed for me to play one of the games. Chose FO3, playing on Xbox. Watched William Strife’s character and beginner guide videos.

For the veterans who love this game:

1. I plan to buy all the DLC before starting. Besides the Pitt being first as per the guide, is there a proper order to play the other 4? I’ve seen some say Zeta earlier because it’s tough as hell, Broken Steel isn’t until after the game, etc. Unsure if I’ve got it all twisted or misunderstood

2. Can I just explore and do side quests or DLC before touching much of the main story? Or does more exploration of the main quest unlock more on those fronts? Trying to understand how to maximize this run to the fullest

Thank you!