Hey Beez, sorry to hear about your WP issues. Did you use a prebuilt template, or did you code you own? Just curious, because WP needs to know the template path to properly find the images. Honestly it sounds like a config issue more than an overall WP issue. I wouldn't mind helping you with setup if you want to take another try at it, but I understand if the whole experience has soured your toward WP. :-(
Upgrading is as easy as clicking a link in WP, they recommend backing everything up before the upgrade but I just tarball up the whole dir, upgrade then del tarbar, never had even the slightest issue.