get him the android, just got my dad one, and trust me - your dad can't be worse then mine.
necessary apps for dads:
some kind of T9/ABC keyboard (I got him smart keyboard). By far the most frustrating thing for older people is their fingers not being accurate enough to type on the qwerty keys.
Gesture Search - he will find this impressive, intuitive, and my dad uses it more often then not to find a contact as he doesn't seem to like the contact scroll in android. I just have it searching for contacts. He loves it.
Vlingo - this one is funny. The only thing my dad really wanted to play with was voice-to-text. He wanted to send texts by speaking. Google voice search is not nearly as reliable as this for texts and calls. You can't beat GVsearch for things like voice searching the internet or getting a map, but vlingo is excellent for voicing sms or making quick calls.
Launcher Pro (or ADW) - stock Android just isn't what people are looking for (I can only speak for motoblur, though). People want a dock. Simple as that. Get him a dock, and only give him three screens. More then that gets too complicated. Also, hide all the stupid apps he'll never need in the drawer (launcher pro feature). This will all make it seem much more usable.
Good luck man, I think if you help him a bit, he'll LOVE the phone.