Likely way more work than you're interested in but on Linux:
Follow most of the steps on this page: https://code.google.com/p/chromium/wiki/LinuxBuildInstructio... then:
export GYP_DEFINES=chromeos=1
gclient runhooks
ninja -C out/Release chrome # May take a while!
./out/Release/chrome
... this produces a build of Chrome very similar to the one run in ChromeOS (we use it for 99% of UI development & testing on our Linux workstations). You can run this and get a feel for the desktop environment, window manager, etc. Similar steps will work on Windows but with use_aura=1 defined in GYP_DEFINES, and chrome run with --open-ash on the command line.If you're in America, I'd recommend trying a Chromebook out at a local Best Buy. Failing that, throwing an old Hexxeh USB build on a USB key and booting it will give you a first approximation, but you'll miss out on things like the proprietary EME extensions that enable Netflix and other little details that make Chromebooks usable.
I got the hexxeh build running fine on VMWare (Workstation, but it should work fine in Player) a couple of days ago.
All I had to do was change ethernet config in the .vmx file as it wasn't picking up the virtual adapter.