Rename the main folder when you uninstall Ares. Example: If it's "Shared", replace the name with "Shared2".
I don't trust Ares at all for P2P, its a pile of garbage, and pretty unsafe. It runs too buggy on my friends computer.
I would only use LimeWire, it's created on Java, so no viruses are created with it, and it's safer/faster.