Trust me, you need to start from the beginning because his best work was at the beginning:
Look What U Did 2 me (CLASSIC) First album
Guerilla Maab-Rise Album (CLASSIC)
Z-Ro vs. the World
King of the Ghetto
The Life of Joseph W. McVey (First real "mainstream" album)
Let the Truth be Told
Cocaine
Crack
King of the Ghetto: Power
Plus, if you like your music screwed, you could get all those albums screwed. But any of these would put you on to the real Z-Ro music
So what album should I start with...