even though HD-DVD is region free, do discs that you buy in other countries (like England), have the PAL speed up like normal discs do? i have some that i might want to buy, but the PAL speed up always bothered me.

PAL does not apply to HD. HD is neither NTSC or PAL, it's just HD.

So, no, you won't have any problems... except for the fact that some HD discs used a sped-up master. I think pro-b and/or Mr. Cinema can probably clarify, but this has been a very small % of Studio Canal titles.

This is essentially correct. There are a decent amount of threads at AVS with more details on this.

The weird thing is, from what I understand, the runtimes on the affected Studio Canal discs are actually correct, which would suggest they actually manipulated the audio track to be a higher pitch. Typically, a PAL disc's runtime would be shorter because it plays faster, hence the higher pitched audio.

I don't know every disc that's affected off the top of my head, but I know these are part of the list:

Total Recall
Basic Instinct
The Graduate
Mulholland Dr.

I believe the Rambo films were also affected.

So what would happen if I were to play these on my US player? The reason I ask is that I was considering tracking down a copy of Total Recall...

You'd hear the sped-up audio. Schwarzenegger's voice pitched up a bit, etc.