I have no idea if there are prior Tom Thumb or Thumbelina movies before this one (actually, I'm sure there are -- I just don't know if they're actually related to it), but this new Adventure certainly features an all-new, all-star cast.
Jennifer Love Hewitt (who's making a cottage industry out of voicing animated heroines) and Elijah Wood (who's making a cottage industry out of playing smaller-than-normal characters) take center stage as the titular leads, ultra-short teens in search of destiny (and quite naturally, one another, though they don't know it yet).
Disney-style antics ensue, as Thumbelina escapes a circus freakshow (she's really small, you know) and then faces forced marriage by the conniving Mole King (Peter Gallagher). Who will rescue her... hmmmmm.
Fortunately, Hewitt can sing -- which helps, because they pack six new songs into 75 minutes of movie. And kids will have fun ogling the moles while adults take interest in the celebrity voices (Jon Stewart, Bebe Neuwirth, etc.) who take supporting roles. It's harmless fun and carries a reasonably competent "message" about finding yourself, being different is okay, and all that Disney crap.
Oddly enough, this isn't completely a Disney film -- rather, it's being put out by Miramax Home Video. What's that got to do with anything? No idea, but I thought that since I noticed, I ought to make everyone on earth read that I did.