Yeah, it's best that OV organize it if he's volunteering, though I can always add some input. 🙂
As is, I think Video Game Characters should be specified which game they're coming from, obviously. Solid Snake from Metal Gear is a different animal completely from Solid Snake from Metal Gear Solid 4 for example.
Anime/Manga characters should be specified which medium they're coming from. Typically, manga is the best way to go, as its the "source" material most of the time. Though more people watched the DBZ anime than actually read the manga from my experience.
Certain characters will need their own specific clarifications on a case by case basis, as well.
But yeah, a poll thread with the choices mentioned thus far should be made, and then we should sparingly introduce each "cross genre" fight over to gauge interest and reaction.