First, did you try to play the game with just the v1.66 version that comes with the Diamond version without patching to v1.69?
If it runs fine out-of-the-box, then use the critical update that MrZork suggested.
If the textures et al. are displayed badly with just v1.66 installed, can you read the disc okay?
If so, you can copy the files directly from the compressed files on the disc into the appropriate folders. Some are bifs that should be placed into the data folder and some, like the texturepacks, are erfs to be placed into the texturepacks folder. There are separate zip files for SoU (XP1) and HotU (XP2) on the disc so check all of them.
If nothing else, by comparing the filenames on the disc vs. those in the folders on your harddrive, you can at least determine if the files ever installed at all. Also, check the filesize of each. It is highly unlikely that if the sizes match exactly that they are corrupt, though I suppose it may be possible. It only takes one byte out of place to corrupt things.
If you can't read the disc (i.e. explore it), then either the disc or your disc drive read head is faulty. Some of the texture packs are huge (like over 200Mb) or they could be emailed.
