Okay.....feeling REALLY stupid now. I looked at the website that Merlin posted, it was like greek to me. and I have NO clue how to do the tasks that Raptor suggests......I am sorry.
The website Merlin provided you with is actually only for experienced users that are interested in shutting down Windows 'services' that they donot require. I believe there is a PDF version as well which is easier to read.
For example, the writer of this guide has 6 made groups. Of which 5 are custom and 1 is standard (Windows standard settings) And the last being the most tampered with and the second good for any user.
Once you have read the intro and did exactly as he told it will make more sense. You can disable, enable or put Windows services to automatic which should free up memory.
However, I suggest you are very careful should you proceed.