We could have a plug-in or built-in option for better physics later on, in the same way that OpenTTD has (though RCT's physics are _perfect_, compared to those of Transport Tycoon, so OpenTTD really _needed_ one). As Jens pointed out, there are too many parks and roller coaster designs out there that would break if we meddled with the physics.
OK, if those are all the files in that folder, you're indeed missing all of the music files, since that is put in css3.dat through css46.dat.
Since you have the CD version, I think you have done a "Minimum" install. Please reinstall RCT2 and make sure you choose to do the full install.