Intresting glitch.. and one that could be caused by several problems, is it possible for me to see a screenshot of what the game looks like to you?
But, i think i might be able to narrow it down to one or two causes...
#1 You are running an incompatible version of Quicktime...
This game uses an older version of Quicktime to play the character animation movies (version 6 if i recall correctly, which is difficult to find on the net anymore), and if you do not have Quicktime installed at all, or if you have one of the newer Quicktime versions, then this could cause the animations to not display... If this is the case i do not recommend installing an older QT version just to play this game... as this can cause more problems than the single one it solves
#2 You could need to update your DirectX drivers...
This could also be the source of it if you are running windows vista, since several old key files to run games released before 04' have not been included in the standard DirectX versions since 06'... running
Microsofts DirectX web installer from their website might also help (since this version includes those old runtime files)