WooCommerce – Great Solution For Small-Mid Size
Magento – Enterprise Solution With Issues
CS-Cart – Best Paid Solution Available to Date
Interspire Shopping Cart – Worth Mentioning
While there are many other solutions out there including Hosted Solutions of all kinds. However I would not recommend them to anyone as they do not have the history of success as these solutions. Safe bet is to go with CS-Cart, as this will have the best export to Oracle and other accounting solutions, as well as the most professionally supported solution.