Photo Gallery plugin

Hi there

I’m building a blog to my duathlon team (http://scosmeduatlo.com). One of our objectives is to sell photos using the blog. I am a bit uncertain whether its better to install a gallery plugin in a page or link the blog to Picasa and display there the photos I want to sell. I want something really simple to visitors to connect to and I am afraid that the second option (Picasa) isn´t so user-friendly.

Can somebody help me with it?

Thanks