Hmmm....well, there are no other buffets in DLR except for the character ones, BUT, if I am not mistaken (and I could be!), I THINK there is a Hometown Buffet right around DLR. I can't recall if it is across the street, but I thought there was one somewhere in the vicinity.
There is a Hometown Buffet on Katella about a mile west of DLR, but we prefer the one that's a bit further - on Chapman about three miles west of Harbor Blvd, behind a Bank of America and See's Candy Shop. Here's a map.
Ah - that's an important piece of information. I've only heard bad things about Captain Kidd's buffet, which is nearby. Mimi's Cafe (adjacent to HoJo's) is great for every meal, but alas, no buffet. Come to think of it, Hometown Buffet only does breakfast on Saturday/Sunday. So not much help here, sorry.