Be sure you research photos of Lake Isabella to gain an appreciation of what you are in store for if you stay there.  The "lake" is actually a reservoir which does have some fishing and other water sports opportunities, but is far from aesthetically pleasing.  It is hot spring - fall and very windy throughout the year.  Hotel options are limited, overpriced, and frankly not very good.  Restaurant options are limited, and somewhat average at best.

 Unless you are into activities that are specific to Lake Isabella, and require that you stay there, you might consider Kernville which is just up the road and far more pedestrian friendly.  Nice hotels, restaurants, markets, boutiques and activities.  If you are camping, go higher into the mountains and explore campgrounds there.  They are higher up, cooler, far less cramped and graced with rivers and creeks, and trees!