Yeah, the audio thing is weird. ALSA actually has drivers for the vast majority of hardware out there, but somehow this doesn't translate into an acceptable userspace experience.

I've never used Hulu (yay, geolocation blacklisting!), but I was under the impression that it used Flash; this is probably why it's so slow. Mplayer, Xine, VLC, etc. can generally handle HD video playback on a reasonably recent CPU.