Echoing mjolinor's comment, but feel free to append with extra info.

Installing the AD tools won't help. `Get-DistributionGroup` is an Exchange cmdlet.

You'll need to either: 

* install the Exchange Management Tools
* or connect to a management session on an Exchange server

The `Get-DistributionGroup` command is supposed to list distribution groups in a domain but I can't get it to run on my server.

After some Googling I found that `Import-Module ActiveDirectory` needs to be run first, but what I get when I run that is:
    
> Import-Module : The specified module 'ActiveDirectory' was not loaded because no valid module file was found in any module directory.

My questions are 

1. How do I install this module into my PowerShell module directory? I thought it was supposed to do this automatically
1. Once I have it installed, do I just run `Import-Module ActiveDirectory` and then I can run `Get-DistributionGroup` to list my dist groups?