I have an understanding of basic HTML code from my highschool days but was recently thinking about making an actually halfway decent website. I'll elaborate further in just a moment. Here is a basic drawing of what I would like the page to look like.

I hope its self explanatory... and no, in case you're wondering, it's not a how-to-draw website.
The Blah's are the text of the individual pages, which will be different on each page. The lines on the left of the blah's will be my menu. This is the bit which I need help on. When I do HTML I can do each page, but if I add another, I'll have to update all the pages to have the link.
Say I've got four pages which all have these links down the side:
September 9, 2006
September 10, 2006
September 11, 2006
September 12, 2006
And I go to add September 13, 2006. I'll have to go back to all four pages and code in the link to the new page, so they all have it, so anyone can get to the new page from the one they're on. Is there any way to have all the pages realise there is a new page all at the same time? I understand this may not be HTML any more, but that's alright with me. I can learn. I think.
Also, I'd like a comment's page where people can... well, leave comments. Is there an easy way to do this? Such as, for example, having a form for people to type in their information... eg. name, their site, email (optional) and comments, with a button for "post" and "forget" and I'll be able to edit them or delete them if they're spam, etc.
Sorry if this is over board, you asked me to be descriptive in what I wanted. Oh, and sorry about the terrible picture.
