PPC Equipped "Classic Amigas" can easily play low resolution (320x200) AVI's, maybe skipping some (but not too many) frames now and then.
On larger resolutions, Frogger skips most frames (unless you add NOSKIP tooltype, which disables frameskip and sound)
AMP2 seems more stabile, but has no frameskip, instead, it skips the sound...
Larger resolution AVI's are really too much for any classic Amigas, unless you're ready to sacrifice sound (Frogger) or make it skip a lot (AMP2)
But on 600MHz G3... They run very nicely :-)