If this is your first trip to Cabo San Lucas you must understand that when searching for a place to stay that there are resorts in San Jose Del Cabo, the Corridor and Cabo San Lucas. San Jose Del Cabo is about 35 minutes drive to downtown Cabo San Lucas. The Corridor is the stretch of land between San Jose Del Cabo and Cabo San Lucas. If you want to venture into Cabo and go to the bars and nightclubs, I recommend staying in Cabo San Lucas. San Jose Del Cabo is more of a quiet artsy town. Most beaches are not swimmable beaches. Therefore the resorts have massive pools.
My top choice is the Riu Sante Fe. This resort is fairly new and it is strictly all-inclusive. This resort caters to all ages but it does have a "young vibe". This resort is about a 25 minute walk to downtown Cabo by way of the beach. You can also catch the local bus at the main entrance to the resort. It will cost you about $2 USD. Riu Sante Fe has swim up pool bars, kids club, several restaurants, entertainment, spa and gym.
If you choose to do an all-inclusive you do not necessarily have to rent a car for the entire vacation. These resorts have enough activities that you may not want to leave. I recommend only renting a car if you need one. If you speak with the concierge at both of these resorts, they can arrange to have a rental car brought to the resort for you. Public transportation is always less expensive than renting a car in Mexico.
If you are a local, both of these resorts offer "Day Passes". We have found that sometimes it is cheaper to book a night than to pay for the "Day Pass". You check in at 11am and then stay until 3pm the next day.