hmmm...another mini distro war.
I have both gentoo and kubuntu.
For ease of maintenance (you don't need to know the underlying linux) and ease of use kubuntu/ubuntu rules.
For flexibility and learning linux gentoo rules. Gentoo is also easier to have bleeding edge software. I have a desktop that has fluxbox,kde,gnome,enlightenment e17and fvmn all installed and working with little effort (well except maybe e17).
On a laptop, it depends on the power of the laptop. If it is an older laptop, kubuntu will be easier on you because the absence of compiling everything.