In response to the OP's questions: (For the sake of answering, I am assuming that a blobber has to be first person for the dungeon component and is generally turn based combat and the movement is grid based).
- Best blobber of all time, or at least some that immediately stand out? My favourite is the original Phantasy Star, but this is influenced by what I remember as a child and the fact it mixes both top down world exploration with dungeons that are in the classic Wizardry form and mixes more broad exploration with obscure puzzles, rather than being limited to a single semi-linear dungeon. Eliminage Gothic and the Dark Spire if you want something more recent and possibly more accessible but also much more punishing particularly in later levels. If we break the turn based rule and allow real-time fighting, then the original Lands of Lore and Dungeon Master II were fun. If we break the static movement requirement, try Paper Sorcerer. If we break both conditions but keep to games set predominantly in dungeons then Ultima Underworld II or Daggerfall.
- Best M&M game(s)? M&M6 was my favourite M&M (bearing in mind this is real time combat based), Xeen is also good (turn based). Of more recent, Might and Magic X is okay but pretty broken if you know what you are doing.
- Best Wizardry game(s)? If you want to just play the basic mechanics, Wizardry 1 is as good as any. If you want a good mix of the later stuff they incorporated then Wizardry VII or Wizardry Gold.
- Any other good blobber series or games that are worth looking into? Apart from the above, just for the ridiculous name, Dinosaur Resurrection by Falcom. I know it is not everyone's taste but I like the Wizardry Xth series also redone as Operation Abyss and Operation Babel. Going back a bit, Realms of Arkania (Star Trail and Blade of Destiny) - as I mentioned in another thread, I was totally scared off the remakes during the early access, but I suppose they have had enough time to iron out the issues....maybe.
- Any tips for enjoying blobbers, either game specific or not? A good blobber will make you wander to and from the inn until your characters are ready to face the next challenge; from this perspective you can't rush through. I would therefore recommend playing in 1-2 hour batches, rather than just going at it incessantly. With Wizardry and it's clones, you need to remember part of the fun is in character creation and development, so don't ever feel the need to rush through that side of it.