The usual problem about having blog and forum altogether is being confused about the content on both platform. You will have repetitive content on both blog and forum. Some may prefer to write comments instead of joining the forums. And so on.
Judging from the content you're planning to do as stated in your first post, blog seems to be the best option. Forum is too complicated for that kind of content. The only blog software I will recommend is WordPress. There's always an option to go on money-spending spree. I have a website running WP.org blog, with free theme (my tech modified it a bit). Basically I mean if you're not too concerned with themes and ads, you can just choose a free theme and tweak it to make it personal.
Good luck, Mr.Panos! ๐