I got my husband's aunt a netbook with windows 7 starter and spent quite a bit of time customizing it:
* placed shortcuts to skype, picasa, chrome, windows mail and word starter right on the desktop.
* I renamed the shortcuts to "pictures", "mail", "internet", etc.
* I set the chorme homepage to google, so she could easily "write and search", I created bookmarks for the key things she needs (news, cinema... and she really wanted facebook!) and put them on the toolbar on top.
* I opened up accounts for her, and set chrome to remember all IDs and passwords (and I used the same all over)
* I customized picasa and windows mail so that no unnecessary buttons and options were there, created an address book to facilitate her writing to the family, uploading to facebook could become automatic, etc.
She's happily surfing the web and posting on facebook now
and so proud to say she now "has" the internet.
A friend of mine, went the other route and got her 80-something mother an ipad, which he also customized as he could to simplify. She learned very quickly (didn't need him to set everything up for her like I had to), and communicates with children and grandchildren across the ocean with no problem.
I think it's more a matter of how you set up the device than what device you choose. I do believe that touch screens are more intuitive than cursors, but I think the virtual keyboard may be a little more difficult to use. All in all, though, you can't go wrong if you set it up right.