Dunno that Im an expert.
I guess it depends if you want to study a subject that will earn a good living, or if you want to gain knowledge. I personally studyed a vocational topic, ie accounting, and wished Id studied something useless but interesting like arts.
As for working at a University. A degree in something, anything helps greatly. Theres facets to University employment
* Teaching - ie in a subject you have a degree or higher
*Research - in a subject you are studying or have a degree or higher
*Administration - which is split into two. Central Administration and administration in the faculties. Whichever one you choose you may end up pigeon holed for life.
Faculties Administration involves dealing with students. Central admin often has nothing to do with the day to day teaching and research role of the Uni. Depends what you like really.
I work at a sandstone University, the equivalent of the USA Ivy League, or the Oxford/Cambridge type institutions in England. It may well be different in a more vocational based university.
Ah, what a lot of waffle.