You can redirect the domain rousseauscorner.com to the store URL http://rousseauscorner.com/store/
using some redirection method such as iframe redirection so the address bar would remain with domain name only or use some other direct redirection method such as with .htaccess.
If you wish the store website to be loaded directly at http://rousseauscorner.com/
you can transfer the website to the main domain folder following this official WordPress script tutorial:http://codex.wordpress.org/Moving_WordPress
If there is anything else we can help with, feel free to write.