Showing the last comment

Fist of all thank you for the link.

Unfortunately I’m not that good with page queries and I cannot figure it out. Can someone help me with a little bit of explanation on how to do this?
This is the code for the page where I want to show the last comment from one of my posts called “Greetings” with ID of “greetings” how can implement this?

[moderated: chunk of code removed as per forum rules – please use a pastebin]

Thanks a lot