.mp4file container and one of the following codecs:
h264, vp8, vp9. This way your video will be streamed in web browser without any additional transformation.
64GB, but it can be easily configured in the instance settings.
FullHD (1920×1080)if your PC supports hardware acceleration and
HD (1280×720)if your PC doesn't have any GPU (even Intel HD) or your network bandwidth is limited.