Computer memory - how to check on remaining and freeing up

[maggiethecat]

Know there has been a thread on this but could not find.
I need to back up my iphone/ipod and my pc does not seem to have enough memory space to do this.
First I cannot remember how to navigate to check remaining space and second can I do a clean up or try to remove files?
Also, is adding bought memory fairly straightforward.
Technology has pretty much passed me by!

This from Microsoft via Google

1. Open Computer by clicking the Start button Picture of the Start button, and then clicking Computer.

1. Click the hard disk you want to check.

The total size and available free space appear in the Details pane at the bottom of the folder window.