Boy, some of you need to consider that you could be the person on the other side of the monitor
reading these nasty reviews without constructive improvement suggestions.
I am assuming you are a DIY webmaster,
Not horrible (have seen worse).
Slideshow on Home Page
Unique in that people usually have all the images positioned the same way. Maybe slow down the rotation. I'm finding it a bit fast.
I would have to agree the background image in the side navigation is making it hard to read the menu but I get why you tried this. Maybe move it over on the right on it's own and make the navigation colum a bit smaller in width?
Your side navigation uses images. Search engines don't read images, yet. So for improved SEO rethink using images with text in them for the navigation. You could recycle the item background circle and the on mouseover image switch.
All your navigation should use absolute links for better SEO. i.e. http://www.domainname.com/page.htm
You have also missed the added SEO benefit of using the link title attribute.
You have some of your pages named page2.html for example. Not good for SEO. These need to be named with a keyword or two that is what the page is about.
Yes you need a footer complete with contact information. This is an opportunity to add usability to each page should the user decide to print out your page to give you a call later if they are doing research for their home construction and collecting contractors to contact for a bid. It also helps with your local SEO.
You haven't used the heading tags available for added SEO and usability.
Pages with List of Links
You have some pages with lists of links. So these do not look like link farm pages introductions and descriptions for the links need to be added.
You have used some antiquated coding and quite a bit of inline styling. Cleaning up the old coding and moving your styling to an external stylesheet will improve the download speed of the pages plus make it easier the maintain in the future.
Google has a PDF: Search Engine Optimization Starter Guide
you could read.