Any ideas where this (user) area came from and how I can remove it?

Run ppm help and have a look at the ppm area init *area* documentation contained therein.
That might give a clue to how it got there and how to get rid of it.

It's not clear to me how the removal of an area can be achieved - or even if it can be achieved.
If you have trouble removing it, instead try ppm area init user. (Not sure if user needs to be encased within ** as per the documentation ... you'd just have to try it and see.)

Cheers,
Rob