Ushi No Tane - Harvest Moon

Is there much of a difference between FOMT AND MFOMT? (besides bachelors/bachelorettes)

Well, other than the bachelors, there are a few minor differences. One, you can use the mirror in your house to change the color of your overalls.
You can sell items to Won in this game, and he's even a secret bachelor (in case you didn't know. Same with Gourmet and Kappa).
The gamecube game that corresponds with this one is Another Wonderful Life, instead of A Wonderful Life for FoMT.
Umm... you also have a farm degree, which I believe is new. It's just a thing that keeps track of your game progress.

and If you marry the Kappa, your child is normal... O.O
That's no different from the boy file but ... you get to marry something ... soo.... @__@