do a restore back to before the attempted install and do it again.
Manually delete all that you find belonging to the SIMS game and try again. It'll be C:\Progams\EA Games most likely.
That's 2 things I'd try.
Minimum System requirements:
Operating system: windows 95/98/xp
Sound card: directx 7.0 compatible
Processor: 233 MHz
Directx: version 7.0
Memory: 64 MB RAM
Input: Keyboard, Mouse
Hard Drive: 1.4GB
CD-DVD: 4 speeds