You can download something like CCleaner and ask it to clean up your hard drive. Don't use the registry cleaning function of CCleaner (or any other registry cleaning utility for that matter). You can also right click on the drive letter in explorer, choose properties, then run disk cleanup.

 

Probably not down to the amount of files you have, Stay with me now

Close all your programmes so you only have your desktop.

Right click on the blue bar along the bottom of your desktop

A menu should appear,

click Task Manager

You will see a list of numbers with Colum's

Image Name, User Name, CPU, Mem Use,

Click on the CPU Colum twice
This will re-organise it underneath

Under the Image Name
System Idel Process, should now be first in the list on the right hand side

If the Number in the CPU Colum associated to this is low,(99 being perfect) it means your machine is using all its memory while running nothing.

In other words it’s using all its power and memory just doing nothing.

Could be a problem with Ram,
Could have software running in the background that’s taking everything up
Could be a virus

Try that software recommended in the other post, because your laptop needs a service.

 

Here's a guide on what to check and do:

http://www.techsupportforum.com/f174/is-your-pc-running-slow-247566.html