for offline webpages I was just saving from my browser and reading directly on the irex DR. then I got a little smarter and took a series of pages saved from my browser and create one *.prc file using mobipocket creator. recently I was turned on to
http://web2fb2.net/
which I like a lot for quick saves to the DR. It requires FBreader on the DR to open the fb2 file.
I have found the need to save this
http://www.geocities.com/CapitolHill.../contents.html on the DR. I used HTTrack Website Copier from
http://www.httrack.com/ to mirror the site on my hardrive but when the native DR and FBreader both could'nt open it I imported the folder with the mirrored site into a chm creator program and used FBreader to read to open the chm file.
another thing I do when mirroring a site is impractical is use adobe acrobat pro as a web browser appending links that I want ignoring the rest. I then run the resulting pdf through mobipocket creator.
I don't like using my reading glasses. that's why I avoid using pdf's the letters are too small. if you don't have my eyesight problems you could just use acrobat pro as a browser and append any weblinks. then save the pdf to the DR.
with my limited knowledge I have tried to find the quickest way from point A to point B. I just wish for a mobi/epub/fb2 creator application that had a built in browser with an append links feature.