What are you planning to do as you fly?
Single line kites can be attached to an anchor and then mostly ignored. (That doesn't mean abandoned, they need to be supervised and occasionally adjusted if wind changes significantly.) Children like to run with smaller single line kites, but if you need to run or flail your arms that's usually a sign that something needs adjustment. Generally they're like a banner or pennant, put it up in the air and see it from afar; they're great for groups to mark where you are on the beach. If your goal is to sit on the beach, watch the waves, eat your picnic, and occasionally look up at the kite overhead, you want a single line kite. Large kites cost more money and also require better gear, such as sand anchors, and they're probably more money than you want to pay. Generally the most difficult part is adjusting the kite for the wind, often there are some knots on the bridle that can be adjusted based on your wind speed, but once it is up you're basically done.
A multi-line kite (dual or quad) needs to be actively flown by a person. They are kites where the pilot must be in control at all times it is in the air. The only time you can eat your picnic lunch is when the kite is landed. It takes a little bit of skill, if someone helps you learn you can get the basics figured out in an hour or so, and enjoy flying as an activity. If you learn on your own it can take more time. With a bit of practice people can fly formations and patterns. With a bit more practice (more than one weekend) people can do mid-air tricks to make the kite flip, twirl, and otherwise behave in acrobatic ways. People who are comfortable with it can fly for many hours in a day, but it is time on your feet with some upper-body exercise.
They're both good types of kites, but for different purposes. Many kite-laden beaches have both types of kites flying. Kite shows also tend to have a field of large single-line kites that are up from dawn to dusk, plus multi-line kites flown individually as long as the person wants.
If you decide on a dual line kite, of the ones you listed the Beetle has the best reputation for being nigh-indestructible. Parts can still break, but the kite is durable. There are many other kites, some are lighter, some designed for tricks, some designed for group flying, some designed to be a workout, some designed to drag you down a beach. Try to have someone teach you how to fly. There are many varieties in the $50-$150 range.
If you decide on a single line kite, anything over about 8 feet is going to need a solid anchor. Smaller kites can often be tied to a table or heavy chair. The easiest indicator is the type of kite line. If you've got cheap cotton line it's a small kite, you do what you need get it in the air and tie it off. If it has a rating like 100lb line, 250lb line, 500lb line, you better arrange to have something to anchor it off with plus some training about kite safety. Having a line snap with a few hundred pounds on it can be dangerous, and launching/landing can sever fingers if done wrong. Usually the small kites are cheap, you can find them in the store for a few dollars; the large kites quickly reach hundreds of dollars.