chromium os

Well yes you can but you see this OS is in early stages of development. I would recommend you to go for Ubuntu rather than Chromium OS.
But if you want to try it out here is a guide
Guide to try Chromium OS
Download Chromium OS from here

You Can Try Jolicloud it is based on chromium but better plus you can install ubuntu apps. I'm myself running it. Pls give it a try.
Jolicloud

IMO, Chromium OS is designed to run on bare minimum of resources.
So, it will run in any laptops manufactured these days.
But before you try to install Chrome OS, make sure you really want it. You won't be able to run any windows apps, couldn't play games, as well as, may not able to play High def movies etc. (But, Youtube videos would play just fine).
So, my suggestion is first analyze your requirement and then go ahead.

Chromium is experimental at the moment, I would also reco Joli, but thats only if you absolutely insist on a web based distro, these distros are not the same as the netbook editions of distros though

Best way to try out chromium os is to download flow from hexxeh.com which is made from chromium os. And only use the stable build, usb boot. Download the file (~ 300mb) and use byte copy software ( whose link you would get from hexxeh.com) and byte copy the file in a usb of minimum 2 gb,( it would format the pen drive). boot your laptop from usb and you would be using chromium os in 10 seconds, if you like it, you can install it on your hard disk.
Caution: it's still in beta, can crash and many things might not be working.

Depends, try Hexxeh's Vanilla, if it doesn't work, try Flow. If it still doesn't work, you'll have to build it manually based on your hardware, not easy.