I'm afraid I'm particularly ignorant when it comes to using MS-DOS programs........I can't seem to use DiskImage

From Win98SE I double click on the diskimag.exe file which gives me an MS-DOS looking window. The title bar at the top of this window says "Finished - DISKIMAG".

The window contains instructions for use of Disk Image but no "command line" as described in the associated doc.

Can anyone tell me what's going on and how to get past this problem?!

I'd appreciate any help.