That is so odd. I don't see you doing anything out of the ordinary in that video. I'm stumped on why the game won't let you continue.
If I can't find a problem, I can't fix it. I'm going to upload a video of me playing that spot as well and you will see you're not doing anything different from me. This is baffling. 
Youtube isn't accepting the file that fceux produces as a video file. How do I convert it so it can be uploaded?
Oh , no problem , i'll keep trying different stuff or dumps

And this is what i did when i recorded that youtube video:
Click on "File" > AVI/WAV > Record AVI > name your video

A dialog will appear , you can select your preferred codec (I used Xvid codec for that little video)

Make your longplay/demo,etc and when you're done just click on "File" > AVI/WAV > Stop AVI
And that's all i did

i uploaded the video to youtube without any problem (my video had no audio because i disabled it on the emulator)