Everyone has loved my stainless UF C3's and Uniquefire AA-S1, real tough to beat for the money. I'm just thinking common, cheap primaries...something I'd give to my 82 y/o parents 
I'd say AA would be the best bet unless they want something small in which case an AAA light.
Something like a Fenix E01 or E05 for AAA
For AA - stainless steel C3, AA-S1, Hugsby P31/32 if you can get one with a 1.5V driver nowadays.
Trustfire F22 if you want to spend a bit more.
My DRY: (currently) 1800 lumen... self-explanatory i guess?
I purchased a Jetbeam BA10 a few months ago and it has become my EDC and one of my favorite flashlights. It operates on a single AA Battery and has only 2 modes. Low at 12 Lumens and High at 160 Lumens. The BA series is an economy line for Jetbeam, but you wouldn't know it.
Jetbeam BA10 has a Cree XP-G R5 LED, Type III Hard anodized, AR coated Lens, IPX8 waterproof, silver plated switch spring.
For the average person, this would be a great light, and at $39 Cdn I was amazed at the quality and value. And an 18 month warranty to boot !
I bought a dozen of these for chrimbo pressies, i have several others of this type from various sources as they are great for having around and these particular ones
http://www.ebay.co.uk/itm/CREE-Q5-WC-LED-240-Lumen-Zoomable-Torch-Flashl...
blow all the others away for beam quality and superior brightness and throw, they are actually posted out of Singapore and arrived in a week to UK!
They were £4.09p delivered when i bought them in a dollar listing but for £4.50 delivered you can't go wrong, Aldi sell a lower brightness effort same model for £10.99! How do i know? my mate bought one and is miffed.
Kids love them with the zoom and they fit in a handbag or pocket and can be used on a bike in a tent etc..
M.