For sentimental reasons would be my Browning Buckmark because I taught my kids and grandkids to shoot with it. Lots of great memories.
For selfish me reasons would be my S&W Model 66, 2 1/2 in cuz I shoot it better than any other gun I own.
I would have to keep my old 10-22. One of the very first new rifles I ever bought and has an early serial number. 2-10round magazines and one 30 round mag.