What actors and actresses appeared in The One Day at a Time Reunion - 2005?

There was no official "One Day at a Time" reunion in 2005. The show ended in 1984, and while the cast has done various appearances and reunions over the years, there is no record of a specific reunion in 2005.

It's possible you're thinking of a different reunion, or perhaps a fan-made event.

Can you clarify what you're looking for?