My mum, although doesn't fully realise it, has been reading comics for about 30 years - (yet still refers to me and my comics as if she hasn't)
She only really reads trades now, and I give her stuff over every couple of weeks.
Lost Girls has been hidden away so she can't find it if she ever goes looking for something to read when I'm not in. Needless to say, The Courtyard and Neonomicon have never been passed onto her to read.
I think over the years Sandman and Sandman Mystery Theatre have probably been her favourite books - and she liked Fables so much that she ended up buying them herself from Amazon after I stopped reading it (alhough I did chuck in a few volumes of that, Unwritten and Sweet Tooth for her birthdays and Xmas (the latter two I bought in floppy and didn't want her to ruin (she sometimes has the habit of falling asleep on them, which I don't mind so much for trades that I'll keep - but singles I want in decent condition so I can punt them on eBay if the notion takes me).
Nowadays I think Morning Glories, Locke & Key and Rachel Rising have been the books she has enjoyed most - at least that's the ones she always asks if there's 'a new one out yet'.