1) Has the laptop been cleaned out inside, since it was new?
Physically cleaning the inside out?
I would have it professionally cleaned out. Or if you wish to do so, simply post in a Comment, and I'll give you a link to a free Service Manual, and some tips.
Overheating can cause the laptop to slow down.
If it has never been cleaned out on the inside, it is also a good time to replace the Thermal Paste on the Processor.
Need guidance on this post in a Comment.
2) If a Harddrive is filled to more than 50 percent capacity, the computer slows down. Really noticed, once you go beyond 70 percent capacity.
Clean the Harddrive out.
A) Get rid of unused programs you have installed, or downloaded.
[ Note* Leave Windows programs ALONE ]
B) Remove personal documents you can copy off, and have at your fingertips.
Photos, music, videos, personal documents you have created, documents you have downloaded, etc.
C) Defragment your harddrive.
Click on Start, then Control Panel. Click on Performance and Maintenance. (Category view)
Click on -> Rearrange items on your hard disk drive to make programs run faster
Windows Vista and Windows 7?http://windows.about.com/od/maintainandfix/ss/SBSdefragWin7_all.htm
Clean up your registry. I suggest the free CCleaner,http://www.piriform.com/ccleaner
Need help downloading, installing, or using just post in a Comment.
I use it.
For additional questions please post in a Comment.