Yes, there is an issue with some of these in that yes they're brand names, but there isn't necessarily a generic version of the product.
I don't think "Lava Lamp" works for example because the original inventor called it "Astrolight" or "Astro Lamp", and the people who bought the American rights for it called it "Lava
Lite" (which is the registered trademark). Lava Lamp does appear to be somewhat generic.
According to the Wikipedia page Yo-yo doesn't really qualify either, even though a company with the name "Yo-yo" in it did make Yo-yo's. This is similar to how "Motor" isn't trademarked just because General Motors Corporation has the word in its name.
However again
according to Wikipedia "Cat Litter" is the proper name for the brand name "Kitty Litter".
Likewise with Hula Hoop, which is an interesting one because apparently the inventors couldn't patent it since very similar hoop toys had been in use for 1000's of years (made of bamboo and whatnot - which is where they got the idea). However they could protect their "Hula Hoop" trademark and thanks to their head start and good marketing efforts no one wanted any other brand of "hoop toy". Nice.

Zamboni is named after the inventor, but is also definitely a trademark, although a genericized one now. The general term is "ice resurfacing machine". As evidenced by
Olympia Ice Resurfacing Machines.
Oreos are definitely Oreos and anyone calling any other cooke the same is just contributing to the genericizing of that name. I'm actually surprised people in the south call "soda" "Coke". Coke is a much more specific brand name to me. But language is all about use, that's one of the fascinating things about it.
Novocaine is not actually the proper name for the drug and is in fact a brand name. The name of the drug itself is Procaine. Of course the original inventor did also create the tradename Novocaine, so it's kind of a fuzzy one.
Oh and when I tell someone to "Google it", I really do mean that they should look it up in Google. So far as I've seen other search engines continue to be largely a waste of time.

- Oshyan