Hey so I'm new to speedrunning altoghether, this is the first game I try to run. When I complete the run and review the recording, it's very laggy in some parts even though the game was running fine (~60fps) at the time. Can I still upload the run or can it not be properly reviewed due to the lagginess?

It depends on how laggy your video really is. If there are many parts where the video freezes completely, or if the framerate is very low for an extended period of time, it might get rejected. If the lag is not too strong however, it will probably be accepted.

The best thing you can do right now is submit your video anyway, and we'll see whether it's good enough.

Next time, try reducing the video bitrate (maybe also the resolution if needed) of your screen recorder to make sure you can record in a decent quality.

Thanks, there was a great run that was just completely unusable, and the one that looked better was over a minute over mu PB, so I guess I'll have to just keep on trying!