.mdf and .mds = ?????

Can somebody pls help me with this? I downloaded Twisted Metal 2, and it came like this - 3 files =

Twisted Metal2.mdf (around 700 Mb)
Twisted Metal2.mds (around 1.5 Mb)
TM2Setup [package for the web stub] ( Ihave no idea what the f... is this)

I cannot mount the image - Alcohol 120 doesn`t mount mdf files, but it mount`s mds - OK. But after I mounting it and trying to start it up on ePSXe - nothing happends.....

And I have no idea what is that "setup" has to do with everuthing - I`m pretty sure I downloaded a PSX game.... I tried to run it (after scaning it for viruses, offcource...) but is said that "Twisted Metal 2" should be reinstalled.

Help anybody?

Open alcohol 120%
Click general in the options box on the left.
Under the section "Virtual Device", select shell extension.
Click the ones you need to mount then click ok.

thanks, that worked.