If you want the best with a "simple" but perfect installer => use Bootleg.
- Download all files listed in Bootleg_Mods.htm (included in Bootleg0001B3.zip).
- Install the english version of Final Fantasy 7 and choose the Maximum installation.
- Run BFE.exe (GUI for Bootleg) and select what you like.
- Hit the big red "Run Bootleg" button. (Hint: minimize the GUI to the taskbar)
- Now the real installer is running.
Sometimes you will be asked about special adjustment's, so be prepared and don't go away.
- At the end, you have a perfect installation.
Happy testing...

Edit 1:
Very important: Run the Bootleg as Administrator !Copied from PitBrat (because i have a german windows version):
Set Bootleg.exe to run as administrator.
Right click on Bootleg.exe, choose Properties, go to the Compatibility tab and
check "Run this program as an administrator".
The same procedure should be done for BFE.exe .
Edit 2: Before starting the installation, turn UAC
off.