Definitely the 2300c. I have both as well, and if I were to get rid of a 280c or a 2300c, I would always get rid of the 280c every time. The 2300c has the best of the duo series with being the fastest, largest LCD, IDE and SCSI internal connections, and the largest RAM capacity.

Also, congratulations on the additional family member. I have a 2.5 year old and they can be a ton of fun...and a lot of work (but its worth it)