Turtle Found, Help Please?

My dog has been 'finding' turtles in our backyard. A few weeks ago, she found a beautiful turtle. It is a hidden necked turtle, I believe, but don't know what kind. It has red, orange, and yellow spots covering the legs and face. It's shell was a dark green with no color whatsoever. We had to let her go, after a few weeks, as she wouldn't eat. Just this morning, I found another turtle outside. My dog has been digging up plants, so our landlord put these wired things around them to keep her away. Earlier she was barking and I went outside to find another turtle, under the wires. We rescued it and brought it inside. It has a dark green shell with lighter green splatters on it, but it's faint. It's legs are reddish orangish, and it's face looks like a volcano. It is also a hidden necked turtle. It has little dark marks around it's neck, looking like lines going through it's lips. I named it Killer. We need ot know what kind of turtle it is, and what we need to do with it. I know a picture wold help, but I don't have a camera. Please be serious about your answers, thankies.^^