Quote Originally Posted by tohca
Can you explain the correction, Я уже исправил название этой темы.
I am still trying to grasp the various cases.
Literally it's "the title of that topic", so "that" here refers to "topic" and should agree with it's case and gender.
"Темы" is feminine and genitive. So you take "эта" (fem.) (not "это" or "этот"!) and put it into genetive: "этой".
If you want use any masculine noun (for example "раздел") it would be "этого" (masc. gen.), i.e. "название этого раздела".