Both are $40 right now. So with that in mind, I recommend Ghosts. PvZ is a lot of fun, but most people were just playing it to occupy themselves while waiting for Titanfall. It's community has already shrunk a lot since Titanfalls release. Ghosts definitely has the larger community of the two.
If Platinum was HAND drawn, she'd be on paper, fool. This is a video game. They just made her on screen, no "drawing" involved -Delano7 on BlazBlue