If you want rock-solid stability and are willing to pay for it, go with Apple.
Linux is growing in popularity as more and more people discover that it can do anything Windows can do (and in some cases more) and that you can afford to put more money into high performance hardware - since the software is free.
Windows has the advantage of a huge user base. And a correspondingly large software availability. There are many games that will only run on Windows, but then you said that you were not a gamer.
If I were in your situation (as you described it), I would put my money into a fast processor and a lot of memory and use Ubuntu Linux as my OS. It comes with Open Office (it will read and write to Microsoft Office files - Word, Excel, Publisher, etc.) and is an excellent alternative to Microsoft Office. Microsoft Office may have some fancy new bells and whistles in its newest versions, but Open Office will do all the basics). And best of all, if you do not like Linux, you can always go out and purchase a copy of Windows 7 and Office 2010, because Linux has not cost you any money - except for the minimal cost of media (CD or DVD).
Thank you......what I keep thinking about is....I’m 59, I’m a pretty fast learner, and fairly logical. I’ve had a computer since 1983 (Commodore)...BUT....am I up for learning a new OS? I USE computers...I don’t KNOW them, really. Part of me says it will be good for my brain....another part is a little fearful...any thoughts?
NOTE: (I cannot even figure out why my computer says NO SIGNAL and won’t load Windows - I took off the side panel and cleaned and tightened everything I could touch...still doesn’t work....having to call someone today.)