I find that none of the programs on my computer are taking up much memory and I have run antivir and anti spyware programs and have eliminated found threats but it still says that there is one percent of available free space (in the disk defreagmenter)

How much memory is installed on the PC?

Where are you seeing this 1%? There are two types of memroy on a PC, there is your RAM which is working memory and holds currently active programs and data. Then there is storage memory which is your hard drive and contains all your installed programs and data files.

So what is telling you this and how much total Ram and HD space do you have?

Follow this :
-Right click on an empty place in the TASKBAR
-Choose TaskManger
-At the top choose "Process"
-Order process by "CPU", u can do this by clicking on the "CPU" tab.
-Now look on the topmost process of the list and in its CPU usage "??%" (=99%)
This should be the "Hanging" process and from its name you may know what's wrong..
for example if it is "messenger.exe" then u may have craches in your messenger..
if it's "svchost.exe" your system has a problem..
and so on... anyway try first to select it then "end process" it . If you have any problems or don't know what is it , send its name here and we will guide u .