Completely dependent on your interests. I have been a Mac user since 2009 and am still on the same laptop with one refresh in 2015. It just works.
Open Office is shareware that replicates Microsoft Office. A very useful productivity app.
https://www.openoffice.org/
For musicians, Garageband is a surprisingly full featured recording and production software suited for occasional users or pros.
https://www.youtube.com/watch?v=o0Ft-vgM7Rw
Lots of photo and video creative apps that run great on a Mac without crashing like my Windows equivalents seemed to do.