Hi Chrysta,
I would recommend reading over this article. It has a lot of useful tips and best practices for preventing your site from being hacked:
http://www.mastermindblogger.com/2011/14-ways-to-prevent-your-wordpress-blog-from-being-hacked/
Also you would want to make sure that any plugins you install are from a reputable source like the official wordpress repository:
http://wordpress.org/extend/plugins/
The WordPress community will remove any plugins that are known troublemakers. There are also various security plugins that you may want to use, here is an example of one that might work well for you:
http://wordpress.org/extend/plugins/bulletproof-security/
Hope this helps!
Mike@wpengine
