For Spanish: usually the second-to-last syllable is accented, unless an accent mark tells you otherwise. Letters are always pronounced the same. (So I'll give the Spanish ones a stab...)
Chavez- Array is right. SHAH-vehz (Like Cesar
Chavez, the Venezuelan (?) guy)
Zamora- sah-MOR-ah (MOR
sounds like more)
I've always pronounced Rhea
REE-ah. Did you check the database for prn?
I would pronounce Galatea guh-LAY-tee-uh, and Solaris sol-AR-iss (sol=soul, AR=are).
I have no idea on the rest of them. :S
Edited to add: Rhea
is prn REE-ah in the database. Click on the link.
Riddler: "A hit! And also my favorite vitamin."