Color picker picks wrong colors

I have been designing a couple of websites and logos, and having some frustrating problems with colors. The colors displayed are frequently not the same as the colors I select in the color picker. This happens in two separate applications (Rapidweaver and Photoshop Elements 4), and I don't even think they use the same color picker, so I have no idea what it causing the problem.

I started off noticing the problem in Rapidweaver, and at first I thought it was just because of a built-in gradient in the theme. But when I worked with another theme, it kept happening in places where there was no gradient. I got out the DigitalColor Meter and started checking to see what was going on. The color is correct in the little Color Picker box, but is translated wrong to the website preview. When I looked in the CSS that is generated, I found out that the wrong numbers are being put into the code. They are in general much more red than what I am picking (15-20 units different), which explains why a lot of my bluish and yellowish colors are looking dull.

So I would have blamed it on Rapidweaver, only I found out that the same thing is happening in Photoshop Elements 4. I was working on a logo and I checked with the meter and the colors are off. A few are correct, like white and black and some others that seem fairly random. For instance, one web-safe red that I checked comes out right, but others do not.

I spent $50 already having my video card tested, so the hardware is supposedly fine. The Mac guys don't know what's going on either.

Has anybody seen anything like this before? I can work around it in Rapidweaver because I can edit the CSS by hand in the final product if I have to, but it would be inconvenient not to be able to see the design with the correct colors. In Photoshop Elements 4, I don't know what I could do. It's a big problem when I need to match colors.