My neon shuts down, help!!!

I have a 2001 LE (Automatic) neon, bought in the states, but at this moment I have it in Guadalajara, Mex. For the last weeks I havent used because the engine stops, (It´s happended 3 times in last few months) after having used it for aprox. 2 continous hours, suddenly it lacks power, starts shaking and stops completely, I ied turn it back on inmediatelly but shakes and stops again, after aprox. 30 minutes or more I can turn it back on, and use it apparently with no problems on short trips. But for longer trips I dare not use it.
Any help would be apreciatted!! Thanks!

Run it at night for about a half hour shut it off look underneath if the cat is glowing cherry red then it is plugged need a new catylitic converter