1) On the beach, there will be plenty of places close enough, you won't need a ride, unless you want to. If you're going to the higher end restaurants on the West End - most of those WILL pick you up for free. But ask if you have to arrange for your own ride back - is a common practice.
2) For lunch delivery - sorry can't help, I never considered it. But there are so many interesting places on the beach, I'd really advise walking the very short distance and eating there. You could easily do a different place every meal, and not eat at the same place twice.
For specific recommendations, it would help if you named where you're staying - so can help with good places close by.