Do you have to use a certain difficulty to speedrun NFS The Run? Or can I just play it on any I like? If I had to use extreme it would literally take me years xD

insert obligatory 'I'm new to speedrunning' description I want to speedrun some of my favourite racing games, namely DiRT 3, Grid 2 (though I've not completed either of these quite yet, working on it) and, when I feel up to the task, NFS The Run. Unfortunately, I'm a dirt poor console scrub, and not only do I only have an Xbox 360 hooked up to a tiny monitor, my laptop's also pretty trash. I was wondering about the legitimacy of recording via a phone pointed at the monitor. Is this OK? Do I need to be in shot? Do I need to make sure the camera's picking up all the in-game audio? I know a lot of speedruns are done live on Twitch now, and I'm not going to pretend I'll ever be able to do that: is it OK if the video's just that, a video? Does anyone have any advice? It'd be great to hear from someone, as I'm really feeling like I should and could speedrun these games, especially as barely anyone has, especially 100% runs. Thanks for reading, Roanth Rufry Alfer