they look alright to me, as long as use legacy pixel pipe isn't on.
may need pixel shaders.. if it's a hardware problem use the v1.5.2 plugin, which also works and doesn't use them.
which Tony Hawk btw? i'm assuming 1, probably it's the same situation with all.
Try using Rice video plugin
it's easier to just use v1.5 of pj64 if u have it instead of 1.6
neither are exactly wrong, but the official recommendation would be:
a) select the v1.5.2 video plugin (which was included for just this sort of reason) OR
b) upgrade your graphics hardware.
below is 1.6 default settings on a Geforce3