According to this thread, if there are 4 discs, they are cds not dvds and that the copy protection used on disc 1 is safedisc 3.2x whilst the other discs are unprotected.
To make a lawful "copy" that will run without the physical cd in the drive (which I presume to be disc 1) either-
a) Install the game from your original discs and then use alcohol to make an image of disc 1 using safedisc 2/3/4 datatype settings. Then just mount the disc image on alcohol's virtual drive and play. Note that if it doesn't work, you may need to edit your registry to show the installation path as being from whichever drive letter is assigned to your alcohol virtual drive rather than that of your physical cd/dvd drive.
b) If you aren't comfortable with editing your registry, make disc images of each of the 4 cds; disc 1 using safedisc 2/3/4 datatype settings and the other discs as just normal cds. Then install the game from those disc images mounted in turn on your alchol virtual drive. Once installed, mount the disc 1 image and play.