I agree about taking your time and doing a smaller number of samples very carefully, rather than pumping out a whole bunch of mediocre pieces.
For specific advice: Colors. Your first two images especially are almost hard to look at because of the colors you used. The first one is far too white, it hides the detail and makes the whole thing hard to make out. The second one, your whites are too white and your reds are too red. Real colors are almost never perfect like that.
Im not what number 3 is doing there. It looks like an unfinished piece that was left in accidentally. You clearly show with your other pieces that you can do better than that. Dont put anything but your best in your portfolio.
Number 4 I think is pretty decent. If you spent some time detailing and polishing it you could have something very portfolio worthy there. Specifically, the lighting looks like it could use some work, add some more detail to the furnitire, and do something to make that clock stand out more (its pretty much invisible right now).
5 looks like its taken from 4, which is fine. Turn the shine down on those glasses a little bit. Real things arnt that shiny. The flower is the only other interesting thing in that shot and it could probably use some more attention as well…it looks very sterile right now. The clean scene in black and white with the shiny (not too shiny) glasses with vibrant red roses in the background out of center would look pretty cool. With the little flower sticks you have it looks kind of bland.
Also, you should probably just open up a second email account and post a link on your website. Spam is horrible, but loosing a customer because they just went on to the next guy rather than figure out how to contact you is even worse.
One more thing, gray text on a gray background probably isnt the best way to present your text. Use something with a bit more contrast and a bigger font couldnt hurt either.
I like the actual layout of the site. Its simple, functional, and puts your work right in front of people. Thats exactly what you want to do. The only improvement I would make is include links to larger versions of your samples, put your email address at the bottom of the page as well as the top, and include your email address on every one of your pictures. If somebody is going through portfolios and likes one of your pieces they will probably save it to their hard drive. When they are going through latter they wont remember where they got that picture they like and they probably wont take the time to search for you again.