WordPress every time. Secure, constantly updated and has - as Apple would say - an app for everything! My recommendation would be to self host, and use the free Suffusion theme.
I am by no means an expert, but made the following website for my mums charity;
www.bansanghospitalappeal.org
Still a work in progress....but the options and additions that can be made are near limitless.
(Oh, and a particularly good bonus is that WordPress has a great app for android and I guess iPhone where non technical users can upload latest news articles etc in a really easy, obvious way)
Best of luck