What is Reddit's opinion of Clarissa Explains It All - Season One?
From 3.5 billion Reddit comments

By popularity on Reddit, this product is:

#4244 in TV shows

1 review of this product found across Reddit:

Licensing I believe. Shout! Factory has been going through, purchasing the rights and releasing some of the shows onto DVD.

Angry Beavers, Rockos Modern Life, Hey Arnold!, Aaahh Real Monsters, Hey Dude, The Wild Thornberrys.

https://www.shoutfactory.com/tentpoles/nickelodeon

iTunes is doing similar with some shows, unfortunately they tend to release them in "Best of ..." and sometimes they leave episodes out when they do that. Just like how Beavis and Butthead was released in "Mike Judge Volumes"

https://itunes.apple.com/us/tv-season/the-amanda-show-best-of-vol.-1/id282332523

Rugrats is all available on Amazon I believe, Clarissa explains it all they've only released season 1 of http://www.amazon.com/Clarissa-Explains-It-All-Season/dp/B0007Y08LK

A lot of the game shows will probably never officially be released, but a lot of the more niche private torrent trackers have some. Same with some private nickelodeon forums.