If your computer is telling you that you have "Low Memory" the kind of memory it is talking about is not your Hard Drive storage space. It is referring to the amount of free RAM (Random Access Memory) that you have.
There are two ways to fix this;
1. You probably have enough RAM for your computer to work, why you are seeing that error, however, is because the RAM that you DO have is mostly to ALL USED by programs that are running in the background.
TO FIX THIS PROBLEM:
1st Step - Go to START, select "RUN", and then type MSCONFIG this will bring up your System Configuration Utility from there, go to the STARTUP section, and click the button on the bottom (DISABLE ALL) This will stop most programs that are starting when you start your computer. This will take care of allot of the problem.
(if you aren't to freaked out by all the list of things I would go through it individually and make sure you aren't disabling any virus scanners or programs that you want to be running like MSN Live or Yahoo Messenger)
2nd Step - Right Click on "My Computer" proceed to "Advanced", select "Settings" under the "Performance" setion. Select the "Advanced" section and at the bottom of that page, click "Change" under "Virtual Memory."
In the "Initial Size (MB)" section, SET TO: 1524
In the "Maximum Size (MB)", SET TO: 3048
Click, "Set" and exit out of those windows.
This should give you enough "Memory" to run most programs, If you still have trouble, bring it into a repair technician and he should be able to fix the problem without to much trouble (it's an easy problem for a tech)
2. Buy more RAM; depending on your computer it will be DDR RAM or DDR2 RAM - different kinds of computers need different things
- A program called CPU-Z (google it) can tell you what type of memory you have and you can then buy what you need]
(as a reference 1GB of DDR RAM is around $60-$80)
(1 GB of DDR2 RAM is around $25)
Hope this helps,
Wallace Computing