How do I get the value of a registry key and ONLY the value using powershell

NONE of these answers work for situations where the value name contains spaces, dots, or other characters that are reserved in PowerShell. In that case you have to wrap the name in double quotes as per http://blog.danskingdom.com/accessing-powershell-variables-with-periods-in-their-name/ - for example:

PS> Get-ItemProperty Registry::HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\VisualStudio\SxS\VS7

14.0         : C:\Program Files (x86)\Microsoft Visual Studio 14.0\
12.0         : C:\Program Files (x86)\Microsoft Visual Studio 12.0\
11.0         : C:\Program Files (x86)\Microsoft Visual Studio 11.0\
15.0         : C:\Program Files (x86)\Microsoft Visual Studio\2017\Enterprise\
PSPath       : Microsoft.PowerShell.Core\Registry::HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\VisualStudio\SxS\V
               S7
PSParentPath : Microsoft.PowerShell.Core\Registry::HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\VisualStudio\SxS
PSChildName  : VS7
PSProvider   : Microsoft.PowerShell.Core\Registry

If you want to access any of the 14.0, 12.0, 11.0, 15.0 values, the solution from the accepted answer will not work - you will get no output:

PS> (Get-ItemProperty Registry::HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\VisualStudio\SxS\VS7 -Name 15.0).15.0
PS>

What does work is quoting the value name, which you should probably be doing anyway for safety:

PS> (Get-ItemProperty "Registry::HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\VisualStudio\SxS\VS7" -Name "15.0")."15.0"
C:\Program Files (x86)\Microsoft Visual Studio\2017\Enterprise\
PS> 

Thus, the accepted answer should be modified as such:

PS> $key = "Registry::HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\VisualStudio\SxS\VS7"
PS> $value = "15.0"
PS> (Get-ItemProperty -Path $key -Name $value).$value
C:\Program Files (x86)\Microsoft Visual Studio\2017\Enterprise\
PS> 

This works in PowerShell 2.0 through 5.0 (although you should probably be using Get-ItemPropertyValue in v5).

$key = 'HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion'
(Get-ItemProperty -Path $key -Name ProgramFilesDir).ProgramFilesDir

I've never liked how this was provider was implemented like this : /

Basically, it makes every registry value a PSCustomObject object with PsPath, PsParentPath, PsChildname, PSDrive and PSProvider properties and then a property for its actual value. So even though you asked for the item by name, to get its value you have to use the name once more.