Using Curse to install Minecraft mods

Curse cannot install Minecraft mods. What it can do is manage texture packs and saved worlds, as well as giving you the ability to try out the Snapshot builds that are released periodically. This Snapshots are installed separately from your regular installation.

If you don't want to have to go through complex configuration (you often need to unpackage and repackage the files to install mods), then you can use Skydaz to get one-click mods installers. Hopefully, those work for you.

Alternatively, we have already have a question that covers manually installing mods for Minecraft 1.6.1 onwards.