Which towers are the Two Towers?

[Eomer of the Rohirrim]

Cirith Ungol and Minas Morgul have always confused me so can someone please help me out here.

Cirith Ungol is the one next to Shelob's lair and is where Frodo and Sam end up at the end of the Two Towers.

Minas Morgul is the one not too far away from Minas Tirith. (I know the history, its not that that confuses me)

My 2 questions;

1) Was Minas Morgul the one where the Captains of the West marched to? The one with the Black Gate?

2) And in that case, where is the tower of Cirith Ungol?

Thanks.