I started with phpBB when I first got interested. It did what I needed for a forum. But then i wanted more, much more. Now I am a cheap b*stered and go for the free stuff, then donate when I use something for awhile.
In that vein I starte with Mambo. The learning curve was worth it. When Joomla came along and DH put in their One Click installs packages I switched over. I am happy I did.
With all the support out there and the large amount of hacks and mods for it, I would recommend Joomla.
For blogging I haven't really looked into that.
Other things I have used are vBulletin. Powerful, but expensive. phpNuke and phpBB are free and have just asw much.
Someone recommended you set up subdomains and try the different products out there. That was good advice.
Hope this helps.
Rock on DH!