I want to keep an online BLOG or JOURNAL but hosted from my own webserver.....anyone know of any FREE software that can generate this or any tool that will allow me to post and update BLOGS, and even get viewer comments and stuff too perhaps, but the simpler the better I think....

Wordpress - Very cool stuff.

Wordpress - Very cool stuff.

Is it easy to set up and run or involve lots of messing about with files on the server

If your host offeres cPanel or Fantastico, it's more than likeley got it as an auto instal option.
If not - it's pretty simple to get it up and running, there are literally hundreds of forums and websites offering support.

Yes another vote for wordpres here too, so easy to setup and plenty of plugins.