The Galapagos lie about 1,000 kilometres off the coast of Ecuador, and almost all the land is national park. Visitors walk marked trails at set sites, always with a park-certified naturalist guide. The wildlife has no fear of people, which is the whole point.
We usually suggest a small ship. It sails between islands overnight, so each morning you land somewhere new, including the outer islands that day boats cannot reach. A lodge on Santa Cruz or Isabela suits families and poor sailors, at the cost of range.
The honest caveats are cost and choice. Ships fill a year ahead for the busiest weeks, and itineraries differ a great deal, so the route matters more than the vessel.