A DVD recorder with hard drive is a wonderful thing which can perform miracles *if* you actually need to make use of the features and are "tech" oriented enough to master the learning curve, which is way steeper than any of us here likes to admit. For that matter, even a "simple" DVD-only recorder like the Panasonic EZ-28 is no picnic to operate for the non-tech-inclined.
This business of shopping a DVD recorder for a parent usually winds up being a tremendous waste of time and very frustrating for the parent on the receiving end. If you are very young, and your mother is say 50 years old and uses a PC heavily in her work or at home, you might possibly switch her over to a DVD recorder with minimal fuss. If she is any older than that, and still uses a vhs VCR, forget it. You are far, and I mean F-A-R, better off taking the $200 minimal cost of a decent DVD recorder and putting that money into a two year subscription to the cable company decoder box that has a built-in hard drive recorder with "point to the show listing and click" one-touch timeshifting. There is a reason why this device has wiped out sales of DVD recorders in the USA: it is the ideal solution for our parents.
I'm not suggesting our parents or any older person is incapable of using or enjoying a DVD recorder, but per the wider population in all age groups they will more likely hate it if they are used to a VHS vcr and are not very comfortable with computer-like electronics. I know a couple in their 80s who totally "get" DVD technology and have used it to create a library of TCM movies. I also know many, many others from 40 on up who would not be caught dead with a DVD recorder in their house and have in fact returned several to the stores and opted for the recording cable box. If you don't need a permanent DVD copy of anything, using a DVD recorder is a drag, and DVD recorders are not known for durability. Get a cable DVR for $10/month and let the cable company choke on it when it breaks or upgrade it to hi def when you need it.
DVD recorders are fantastic if you are motivated and need the features, but a complete pain if all you want to do is timeshift "30 Rock" or "The Shield". My own 72 y/o mother is hooked on all the F/X dramas, but makes me copy them from DVD recorder to VHS before she'll watch them (she won't even use a DVD *player*: Queen of the Luddites
). Be sure you know your parent very well before helping them choose a recording option: it saves grief later on.