It takes jumper cables to start my samurai and when it has no jumper cables the lights in dash are dim and will not make the starter operate also the battery is good it's an optima.

as long as your battery and alternator are good its more than likely just dirty or loose connections. are you sure your battery is good? just because its a optima dont mean anything. I have seen plenty of optima's fail.

theres also a special way to charge a AGM type battery if it has ever been ran way down. -Google it-

Have you had the battery load tested, or did you just put a meter on it and it said it was 12+ volts?  A bad battery can/will test 12+ volts, when testing with a meter.

Sounds like a bad ground. 

You said the battery is good....how about the battery cables?

Battery cables have some acid corosion on them so i wiggled them around and the ground is on one of the starter mounting bolts also yes the battery has been tested good but the alternator hasn't thanks Guys for the replys

Remove one battery connection, then run jumper to that connection and other jumper to other post on battery (Do not wire in series).  If the problem is still the same, then you have grounding or hot connection problems.  If problem goes away, then it is either battery or battery connections.
You said the ground went to the starter mount, do you have a body ground also?

yes i do to the fire wall however i cant get it off to reset it the screw is froze solid. Also once cranked I can remove the jumper cables and it runs however I give it gas and it will rev slow and then try to die.

Have you cleaned both the battery posts, and the cable connections?