A few questions:
a) Have you selected USB mode on the camera (the Dimage 7 is slow though as it is a very old USB version 1 speed)
b) Does windows even detect that USB has been plugged in - if you don't see any messages it could be a faulty cable.
If you can't find the Minolta software there are other options.
1 - Buy a CF Card to USB card reader - take the card out of the camera and put it into the USB card reader - you can then see the files as a folder on the computer.
(This will be much faster than connecting the old camera to the PC as the card reader will probably support the faster USB2 hispeed transfer mode).
2 - If you are using RAW format for saving pictures then you will need a photo editor that can read the Minolta Dimage 7 RAW files:
Serif PhotoPlus has had this option for quite a while and older versions are often available to download for free
Irfanview also supports Minolta RAW and is free to download.
CodedColor Photo Studio is another option and there are many more.
Alternatively if you have software that can handle the Adobe DNG file format then Adobe offer a free converter to convert Sony/Minolta RAW to DNG...but that's getting a bit complex I guess.