I watched this movie as a kid and can barely remember it. All I know is there is a boy who gets put into a computer or video game world. It’s not Tron.
This is a long shot, but maybe you are remembering one of the segments from the 1983 horror movie anthology Nightmares.
Nightmares is a live action movie but one segment features primitive computer animation similar to Tron, which was released a year earlier. Emilio Estevez plays a gamer who is determined to reach level 13 of his favorite arcade game. He breaks into the arcade and plays the game all night, finally making it to level 13. The arcade game explodes and computer animated weapons rise out of the smoldering machine and attack him. He is in a life or death battle against the game – both shooting laser blasts back and forth. I won’t spoil the ending.
The company that released the Blu-ray of Nightmares has a clip of the computer animated battle scene on YouTube. Click here if you want to check it out.