quicktime problem

[Brian Fish]

Hi all,
 I'm stumped.  I can't get Quicktime videos to play on my ibook, but they
play fine on my PC.  I'm trying to watch old macworld keynotes and expos to
fill the void until January.  On my ibook, Quicktime opens and says
"requested data" for about 30 seconds and then says "timed out" and does
nothing.  On my PC, the same file opens right away and plays with no
problems.  I've updated my Quicktime to 6.0.2 and just recently upgraded to
Quicktime Pro, but still the same results.  I originally thought that it was
a problem with the links on apple's site, but as I said, they work fine on
my PC.