I'm not sure about the purple guy, but the 'Son of Godzilla' character is 'Leviathan' from Digital Hero #4.
While I'm here, I would also like to see the pictures downloadable from the website. Yes, you can do a 'Save As', but it puts part of a blue oval over the legs. Obviously, these guys were colored and then the oval composited over the legs to fit in with the website background. I'd like to see the original version.
IMHO, of course,