General Purpose Settings - up to 6 minutes
A simple way to ensure that the quality is there is to export to MPEG-4 with:
- H.264 video at 2000Kbits/sec (2Mbits/sec or 250KBytes/sec)
- 320x240 video size (deinterlaced or simply use one field)
- Mono audio with AAC at 64 Kbit/sec (or 128 Kbit/sec for stereo)
- Recommended Sample Rate and
- Best Encoding Quality.
- In the Video Options Main Profile should be checked on and Best Quality (Multi-pass) is advised for best quality.
These settings will be fine up to 800 Mbits aka 100 MBytes. At the proposed settings, any file shorter than 6 minutes and 15 seconds will be within YouTube's 100MB per upload limit.