Pick a favorite era from:

Golden Age of the Sith (Naga Sadow, etc.)
The Sith War (Ulic Qel Droma, Exar Kun, Nomi Sunrider, etc.)
Knights of the Old Republic (video game and comic era)
Darth Bane & Jedi vs. Sith

The Rise of Chancellor Palpatine and training of Obi-Wan
TPM era and training of young Anakin
AOTC and Clone Wars era
ROTS and rise of the Empire era (also including Jabba's ascendancy)
Droids in action: R2D2 and C-3PO, their lost years
Young Han Solo and birth of the Rebellion era

Post-Yavin, the rise of Luke Skywalker
Post-Bespin and Shadows of the Empire
Post-Endor and pre-New Republic (Rogue Squadron era)
New Republic era (Thrawn, Jedi Academy, marriage of Luke and Mara)

Young Jedi Knights era - training of Jacen, Jaina, and Anakin Solo

New Jedi Order - the Yuuzhan Vong invasion
Post Zonoma-Sukot - the Dark Nest era
Legacy of the Force era - the betrayal of Jacen Solo

Legacy Comics era - the adventure of Cade Skywalker

I'm going to have to think long and hard over this myself. I'll leave the list posted without my own pick for the moment. See what you choose.