It depends really what you are looking for, what kind of style.
I can only advise on the things I know, and this are the northern continents (Jaiman & Emer). Because we seperated the settings between two GMs, giving both the possibility also to play on Shadow World.
That?s why I know "Nomads" and, I think "Desert Jewel" and also "Star Crown Empire" onl briefly. For sure it?s they?ve a completly different setting, more nomadic, china, mongolic style. But perhaps somebody else can comment on them.
As the decision for a starter pack, I would prefer fo sure Jaiman. Emer is,for the start, too big in my opinion.
So Jaiman would be your best option. To give you a feeling about the "roots", I would advice to Tanara. That?s one of the best settings I ever read. But, it?s playing in the "past".
And if you fastly would like to start with adventuring, go for Norek. With some minor adjustments that?s the only realy ready to run module for Shadow World. Even if it?s got a little bit the flair of dungeon crawling (like I said, some litte adjustments, and it?s really a nice Shadow World setting)
Keep in mind that for all this campaigns and modules you have to put yourself a lot of work into it! Non is really fully and deeply developed, mostly they are in conflict with them self, and you will find dramtic power level changes! So prepare for a lot of work of yourself if you really wan?t to play a rich and fitting campaign!