Need recommendations for the best printer/scanner/copier/fax machine that I can buy?

color or b/w?

We use a Brother MFC and it works quite well.

Best all-in-one inkjets according to cnet.com

I have a Canon MP830 (not on the list), and I like it a lot.

There is no one right answer to this question. Some are better at some things than others, you did not specify how much price was an issue, etc. Google checkout allows you to compare them and many of them have reviews attached. Go here

Inkjet
we have an Officejet Pro L7500 at the office that uses the HP 88 XL cartridges. Supposedly, these cartridges are supposed to have the best efficiency and last longer than any other cartridge. This is partly because you have to buy the magenta, yellow, blue, black, etc cartridges separately, but it also uses some new technology called vivera. Aside from that the printer prints very quickly and clearly. the model we have has an ethernet jack, which is handy if you have a network to put it on.

Laser
There are plenty of multifunction laser printers, but it gets real expensive if you are talking one that does color. if you want b/w, then there are a lot of options—it just depends on how fancy you want to get.