Some choice favorites:

Freeman in Garou:
"What'a the meaning of a hollow life"

SamSho4 (I am pretty sure its 4.....)'s KO screen:
"VICTOLY"

SNK vs Capcom's announcer:
"HEEEEREEE COOOOMES A CHARENGHAR"

One of the street fighter games (Alpha 2?) the announcer shouts "Go for broke" but his thick Japanese accent makes it sound like "GOPHER BLOKE."

Marvel vs. Capcom had some of the greatest especially from Spiderman's ending.  I'll have to find pictures.

1:"You cannot escape!"
2:"YOU will be the one escaping!!!"
The Avengers, genesis

"I'll stain my hands, with your blood"
sounds like "I stain my house, wis your bra"
Geese, KOF 96(?)

any anything terry bogard ever said

I think Geese says that in CvS, not sure where he said it originally, but I know he doesn't say it in '96.

But in CvS, I always thought he says I WILL STAY IN MY HOUSE, WAITING FOR YOUR BLOOD.

EDIT: Also in SvC, Geese says YOU EMBARRASS ME but it's like he's saying YOU IMPERSS ME as if he's trying to say "you impress me".

Garou:
THE CHALLENGER
AA UU RADDY? BASCHkWOOF
BA-BA-BA-BA-BA-BA-sorray! (Feint string into taunt)

And who can forget, from our ever string wearing Cammy:
CONDOM ARROW