You can try the Windows CE .NET 4.2 device emulator to get a feel of what it looks like. Go to Microsoft's download page and download the Windows CE .NET 4.2 Device Emulator.
The default built-in applications that comes with CE .NET are very lightweight, for example there are only viewer for Office files. But whether these viewers are included in a product is determined by the device vendor rather than Microsoft. Usually the vendor would include some applications that are for powerful than those defaults.
Windows CE applications should run on CE .NET, but if you're thinking of running Pocket PC applications on CE .NET, it will most probably not work. This is because the Pocket PC has additional software that exposes different APIs that are not present on other non-PPC devices.