game coming up but need some help!

OK I have making a game when you are a guy that jumps in to a jungel,
there you fight montrers.
1.But one of the monsters(have only made 2 yet) just dies when he has walked a bit.How do I fix this????(I have tried to fix it hundreds of times thats
the reason for that I only have made 2) :(
2.When you walk to something and tuch it how do I make so you go to a frame then???
I was using this code: onClipEvent (enterFrame) {
if (this.hitTest(_root.ENEMY)) {
gotoAndPlay(gameover);

}
}

Try:

onClipEvent (enterFrame) {
if (this.hitTest(_root.ENEMY)) {
_root.gotoAndPlay("gameover");
}
}

thanks man LOL LOL :)