The best bit of DBZ was when they all got together after the three years of Android preparation and we found out that Mirai Trunks wasn't lying about Bulma and Vegeta getting together. Did you see his FACE when it was revealed that he was Trunks' father?! It was HILARIOUS! =D
Best bit of GT was when one of the Shadow Dragons pulling Pan into his body to steal her power, and Goku, as SS4, not being able to shoot his Kamehaha through fear of hurting her. That was total mosh... I also liked the bit where Vegeta and Bulma are talking about the Blutzwave Amplifier that eventually made Vegeta SS4... you saw a connection between them that, to me, was magical.