Issues installing The Sims: Unleashed!

I am having a huge issue with installing Unleashed, and honestly it’s pissing me off.

I have the original Sims and Livin’ Large both installed on my computer. when I go to install unleashed, I am told to put Livin’ Large back in for file copying. When I do, it starts the installation process then stalls at 2% and doesn’t go anywhere for hours. All my disks are clean of fingerprints, scratches, etc.

What do I do? This is driving me nuts…!:a