if I'm doing an animation in poser is there i can change a mat at half way through the animation? Like if I want vicky to start off looking normal (as normal as she can) and then turn blue or get scales before the animation is over?

Sure.  Assuming you're using Poser 5,6,7:  Find the material you
want to change, and the values such as Diffuse Color or Ambient Value. 
Look for the little 'key' next to each value.  Click on the key and set it to
Animated.

Then you can go to the frames where you want the change, and set
those Animated parameters to the desired value.

Note: These changes are linear, so if you want an abrupt change between
frames 30 and 31, you'll need to set the first value at frame 1, then the
first value again at frame 30 .... then set the second value at frame 31
and again at the end.

In 6 and 7, Poser does you a great favor.  After you turn the key to Animated,
Poser automatically creates a new dial for that value on the BODY of the
figure, or on the prop itself if you're dealing with a prop.  This dial can be
animated in the keygraph just like any old rotation or translation, which
means you can make it rounded (spline) instead of linear if you want,
and it's a lot easier to keep track of.

Thanks so much. This will help me out a lot.

This also answers the same question I was about to post...thanks guys :)

Along the same lines, is it possible to emulate a "morph" between 2 different characters?

For example, have the P7 skeleton change over a few frames into an M3 figure, or M3 to a skeleton, along the lines of the old Dracula movies etc.

Thank you.

Quote - This also answers the same question I was about to post...thanks guys :)

Along the same lines, is it possible to emulate a "morph" between 2 different characters?

For example, have the P7 skeleton change over a few frames into an M3 figure, or M3 to a skeleton, along the lines of the old Dracula movies etc.

Thank you.

One way to acheive this is to pose both figures in the same place and make the human figure more transparent over time, revealing the skeleton, then at the end of the transformation remove the (by now invisible) human figure from the scene.