when should I start the timer and end it?

This is my problem, I had tryed 10 different screen recorder, but my pc its just not good enough and while recording the game lags. My game is a GBA game, so I play in a VBA emulator, the thing is, the emulator has the option record AVI/record sound/record video, and while recording video, it doesnt lags. So: -Can my run be legal without recording the timer? (I would use the timer and share the splits, but it wouldn't be visible in the video)

Hello everyone, I want to enter in the speedrun world, so for now I'll be running Shonen Jump's One Piece Any %. Hoping to get the WR one I figure all the streaming recording thing.