Both of these games uses the battle displays from ancient rpgs, think Earthbound, Shin Megami Tensei, or a numbered Phantasy Star (not online, the original games).
Both of them rely on pretty decent jokes, although Cthulhu, being the second game they made, takes the ham way higher, and as a result is mostly funnier. Even though you never see your charathers in the battle, its still pretty involving, with stat buffs and debuffs as well as mana preservation, although it isn't quite as stressful as the games it's actually based on.
The game helps you along with some major streamlining, especially in the inventory and telling you where to go next, although you can sequence break if you are willing to overlevel a bit.
Although if this is the first time you've played one of these in a while, the game will probbably seem monstrously difficult, especially with its unique health refill feature giving them an excuse to use a set monster encounter rate.
In all honesty, I think you should use PSN, GoG, wiiware, xbox arcade, ceirtain indie releases, a compilation game (I can think of several sega genesis sets that include three phantasy star games, not to mention other awesome things in other genres) to experience this sub-genre in pure form.
This game and its companion provide some light entertainment, but the gameplay "outweighs" it, so you have a system that requires a degree of commitment to come to terms with, but due to the fact that you know it's a parody, you don't really have the motivation.