second one looks a whole lot better,

1) looks pretty good, but your mario doesnt stand out enough, it seems like render like that do not look as good blended but rather "unblended"

2)7/10 (cool background, but very simple)

3) unblend mario, stick just him there and dont worry about blending, basically, stick him on. you text looks pretty cool, and so is your background, but i dont know that a grunge background goes well with a mario pic.

4) stick with your current, its awesome.