It's not hard. I'm 53... this is my first e-reader, I've only owned it a month and for the first few weeks, I was intimidated by the library lending. However, once I dived in, it really wasn't a problem. You only have to download the ADE program once, establish an Adobe ID once and then authorize your computer and then your device once.
After that, it is just finding your book and downloading to your computer and a quick transfer to the device via USB. No worse than downloading a free book somewhere and side-loading that.
Nook 3G/WiFi can do the library books, no problem.
You probably should check and be sure your library does the ebook thing as well as checking formats. My library only offers EPUB and PDF. Which is fine for Nook.
Anyway, don't feel outdated... I don't have much for the way of "tech" gadgets myself. I only have an antiquated Tracfone for a cell phone.