Any DC/Marvel titles with Greek/Roman mythology?

Such as Wonder Woman 210 when she faces Medusa or Thor Annual 8 where Loki and Thor are in the Trojan War with Achilles, Paris, etc.?

Wonder Woman is the obvious one. If you go post crisis, pre 52 there's a heap of stuff practically soaking in Greek Mythology. The Sandman by Neil Gaiman also touches on greek mythology time to time, but that contains nudity and coarse language as well as other things such as torture and gore.

Batwoman also had an arc in which she faced mythological monsters.

Hulk and family fights lots of Greek mythology in and around Incredible Hulk 622. In Incredible Hercules they reference the labors of Hercules and him lifting the heavens.

Wonder Woman, pre 52 and post, is full of references to Greek myth (naturally). Hercules in Marvel also comes to mind.

The entire New 52 WW run is heavy in greek mythology.

Hercules from Marvel

Primarily you should be looking at Wonder Woman since DC and Marvel have sorta called dibs on different pantheons, with DC taking Olympus as the primary. (Though Marvel do try hard to keep their Greeks going).

Another sotyr you might want to look into is the New 52 Batwoman: Worlds Finest trade, which features WW, Medusa, a Minotaur and Pegasus (not pretty), Nyx and Cleto.

That said, WW has with the New 52 seen the looks of it's Greek Gods modernized, like these:

Current superman/wonder woman--Superman "owns" Apollo, God of the Sun..