1995 Isuzu rodeo will not start battery is in good condition

I had the same problem as you. Thought it was starter or battery,,,it was neither. I kid you not, I figure this out for myself and problem solved. I did not have the tailgate window locked and it took at least 30 attempts to start. When I locked the tailgate opener located on the far left of dashboard, never a problem,,,, I pulled out the operator's manual/remote control/vehicle security system manual and to my surprise it confirmed. Here is the exact quote from manual "While armed, the system is triggered when a door or the tailgate window is opened. When triggered, the vehicle's horn sounds, and the exterior and interior lights flash. PERHAPS, MORE IMPORTANTLY, THE VEHICLE'S STARTER IS DISABLED AT THE SAME TIME, PREVENTING ENGINE START!!!" Please let me know if this solves your problem or you already went there..