Its the full duke nukem 3d game withe Atomic expansion.
Theres also a plutonium expansion for it but i can't find it at the moment.
The plutonium pack is just the expansion, for people that bought the original release without the 4th chapter. That is what seperates the atomic pack from the normal game. (To my memory.)
I have Life's a beach back home, and duke it out in DC and also nuclear winter.
Lifes a beach is the best if I recall correctly.