Windows Power Shell is a version of a command line interface on steroids. You should be okay installing it (what version of Windows are you on).
As for the ports, it gives you that notice so you know what is needed. You may need to also go into the configuration and enable TCP/IP or Named Pipes, depending on your usage - even on a local computer.
You might do a Google Search on installing and configuring the 2008 Express as it can be a bit daunting.