Well, I could answer all three by stating, "Don't build your web site in Fireworks." FW is a graphics app and prototyping tool. Most of what you are asking about is much better handled by proper web page editing tool like Dreamweaver.
That said, Questions 1 and 2 can be resolved using the "link" Component Symbol and then exporting your file as CSS and Images. Incredibly over simplified answer, but here are a couple articles that cover the process:
If you're using CS5, the enhancements listed by Matt and Michel are already part of FIreworks. If you're using CS4, you'll need to download the enhancements that are part of the article.
The answer to Question 3 is not within Fireworks, unless you're able to find one of the templates that does what you want. More likely, a lightbox or Spry solution or Project VII extenstion is more appropriate.
Regardless of which you chooose, you've got some reading ahead of you. Good luck.
Thank so much for the answers. I find dreamweaver to be a little bit more complicating than fireworks, which is why i design with fireworks, but I am on my way to studying dreamweaver so I can finally make my website go live.
I have one more issue. Whenever I preview the web pages from fireworks on a browser, the background does not fit onto the screen. There is white space on the left side of the screen and on top of the screen. How does one fix that problem?