Can I delete these folders? (Space issues!)

[lister]

My C Drive has only about 800 MB and it is creaking at the seams.

Do you reckon I can delete these folders in the screenshot?

To make it easier I listed the folders below so that perhaps someone could just quote my message? THANKS!

Common Files * Are these just surplus files?
Microsoft Games * Never use these
MSBuild * Are these older builds that can be deleted?
Reference Assemblies * Not sure what this is....
Windows Journal * Not sure what this is....
Windows Mail * Never use these
Windows Media Player * Never use these
Windows NT * Not sure what this is....
Windows Portable Devices * Never use these
Windows Sidebar * Never use these

THANKS!

 

[logicearth]

No and deleting them would not bring any more space.

 

[karlsnooks]

Lister,
What you can do is:
Control Panel | Programs and Feature
Now uninstall any programs you don't want or need.

Control Panel | Programs and Features | in the left-hand pane, click on Turn Windows Features on or off
Turn off that which you do not use.

WIN | type DISK CLEANUP | ENTER
WIN is the key with the wavy flag.

WIN E key combo | Open the C drive | in that long bar at the top, type %TEMP% | select all | delete all
If Win 7 complains that a file can't be deleted, then just skip the file.

Download, install and run the most popular free software, namely, CCleaner:
CCleaner