I really think you should evaluate a CMS of some sort -- and phpnuke ain't it.
If you want your site defaced, choose phpnuke.
Now, as for ease of use, it really depends on what you have available on the server.
mod_perl? metadot or webgui. metadot is a pain in the butt to get running, but, is quite nice, has the wysiwig stuff built in. Webgui is one of the few cms's that has the capability for clean URLs (plainblack.com) They run on a number of large site's Intranets, but don't have a lot of front-end exposure. Metadot runs one of Nasa's sites. Another one that comes to mind is Mason, however, that might need more work than you want to spend. A few sites that run mason.. umm... Amazon.com, salon.com, bizjournals (you know, those city business newpapers), live365.com, rent.com (ebay's latest purchase)
php? mamboserver, xoops, typo3. typo3 is quite comprehensive and does pretty well. Mamboserver runs porsche brazil and a few other big sites, but, get over 100k users and kawhump. Xoops is very well designed, but, they missed the boat on a few things. Novell runs a site on xoops. Typo3 ran on a few high profile sites when I looked at it, but the author disliked adult sites when I first looked at it. He has since changed his stance and I haven't looked at it since.
Can you run modules? Midgard comes to mind with Spideradmin. Takes a little time to get used to it, but, if you want a very custom solution, Midgard is a framework that you can build a CMS on top of. SpiderAdmin, Aegir and another one come with it. They also have a TownPortal demo which is pretty much an out-of-the-box ready to go site.
Got plenty of ram? Openacs is quite good -- although, I just dumped it in favor of writing a CMS the 'proper' way. I spent 18 months working with it, and it is really well designed, really well developed, somewhat well documented and has some great guys behind it. Greenpeace runs openacs, sony's news site, vtec.net for you honda people.
Want to run a j2ee product? Teatrove (yes, the one that disney's go.com/espn was powered with)
Zope/Plone is quite nice IF you can get your head around their structure. Out of the box, they have some pretty good stuff. odsl.org is a large site that uses Plone.
Also check
http://www.cmsmatrix.org (a little biased since it is run by the people at plainblack/webgui)
Have a few bucks? citydesk by fogcreek is pretty nice.
For pdf, get openoffice.org -- writes .pdf files right from there, looks almost like Microsoft word -- and it's free.
If you were considering phpnuke for ease of use, then I would take a look at mamboserver or xoops. From the download to the point where you have a reasonably capable site, these are the ones that will get you running in the least amount of time. They require little in terms of software on the machine.
I've looked at more CMSs than you can imagine and written plenty of one-off CMSs for clients.
http://www.metadot.com/metadot/index.pl (metadot, click the dog's nose)
http://www.plainblack.com/ (webgui)
http://www.masonhq.com/ (mason)
http://mamboserver.com/ (mamboserver)
http://xoops.org (xoops)
http://typo3.org (typo3)
http://midgard-project.org/ (Midgard)
http://openacs.org/ (openacs/aolserver)
http://teatrove.sourceforge.net/ (teatrove)
http://plone.org/ (Plone)
http://www.fogcreek.com/CityDesk/ (citydesk)