No worries, I got this one...
If you have just installed a fresh version of SOF2, the violence lock is default for off (meaning there will be violence). If I was to buy this game for my kid (I don't have one yet, but just pretending here), I would personally install the game and put a password in the lock field to turn it on. Then when my kid plays the game, no blood... I guess, never have seen it with it off, so I am assuming here.
So unless someone purposely added a password, you will see violence... but also remember that this game isn't really very gory. Maybe a blood splat here and there, most previlent with the shotgun
And, if you are an 8 yr old playing behind a parent's password, I'm going to leave it up to you to figure out how to remove it. It is quite easy actually..
Hope this helps.