looks pretty simple...just pick the 1 u like then download it and install it on ur webspace...and thats it...if u want to customize it more you can
most templates and CMSs that ive came across are like that...
if ur making a website i would go with a nuke site or vbportal and then customize your graphics or colors from there...its fairly simple to do...
right now im in the middle of a big site rebuild and we are starting from scratch and may end up building our own CMS
ive used
http://vbportal.com for the past 4 years and have been very happy with them...they are intigrated with vbulletin so the forums are done just had to edit the colors and some of the layout for custom side blocks...its realy quite easy once you figure out what you want to do
ive used phpnuke and post nuke and they were easy to understand too and there is a huge customize base out there just like vB but nuke uses phpBB which sucks as a message board but a good start if you want to learn and then you can go from there