I can recommend a 2bd/2bt condo in a great location in Waikoloa Beach Resort (terrific price, so don't know their schedule); renting was very easy with them, and I hope to go again (http://www.vrbo.com/413069). There are several condo complexes in that area, all with nice pools; the beach at "A Bay" is very nice, and there's a nearby fast food court, grocery, and other shopping and dining in the Kings center and Queens center. Also a short drive to lovely Hapuna and Mauna Kea beaches from there. Oceanfront condos are fewer and more expensive than Maui, but you might be able to find one. (Try the VRBO filters: http://www.vrbo.com/search/usa/hawaii/big-island/kohala-coast?bedrooms=2&location+type=Beachfront)

On the Hilo (VNP)side, you might consider Volcano Village and the surrounds vs. Hilo, even if it is only ~25 miles away from the park. We've only stayed in a studio and a room in a B&B there (way too small for more than 2), but there are many lodging options there. Your kids might like the free zoo with a white tiger in his own lush garden (the tropical setting is gorgeous), just at the base of the road from Volcano NP into Hilo. http://www.hilozoo.com/

I agree with staying in Volcano Village. That way you can have the park early morning and then in the evening and explore other areas in the middle of the day when all the day trippers arrive. Keep your park pass, as it will also give you admission to Place of Refuge on Kona side.

FYI-There are NO beaches associated with any conods on Big Island. If you want a beach, then pick a hotel like Fairmont Orchid or Mauna Kea (Mauna Lani is good too).
However, Condo's are definetely a money saver!

sorry daisee, but that is simply not true.

there are some properties that offer beach amenities, priority parking etc. Not all, and one must be diligent in understanding what is available as a condo renter, and beach access is certainly a perk offered by a few condo associations.

All beaches in Hawaii are pretty much considered "public". Getting physical access can be another matter.

No "pretty much" about it; it's federal law.
http://seagrant.soest.hawaii.edu/public-access-rights

I would check for condos in the Kohala area. I rented a property through vrbo in the Waikoloa Beach Village last June. There's less vog in the Kohala area and the beaches are nice for swimming, playing in the sand, etc.

I think the best place to rent a condo is probably in the Mauna Lani resort area. The beaches are very nice, there's snorkeling, and you are closer to both Hapuna and Mauna Kea beaches which are have great sand. The condos in that resort area were a little out of my budget, but I definitely preferred that location to the Waikoloa Beach area.

We had better snorkeling south of Kona, so we drove down there a couple of days for the snorkeling.