My computer is too slow and it's not working right . What could be wrong ?

I have just spent most of the day cleaning my XP system in an attempt to sell it.  Yes, it is slow.  I use these three programs rther faithfully:  CCleaner; Glary Utilities; ( have the pro version) and Wise Care.  All are free to use.  Thought I would offer this as a suggestion.  I am currently using Win7Pro and yes all three programs are on this computer.
 
I just saw today on the Internet an advertisement wherein this program is offered for free and listed peoples comments how good it was to get your old computer running faster.  Speed Up  Please do not fall for that as it shows you what can be cleaned, then you have to pay for the extra download.  The three programs previously stated to an excellent job.  WiseCare removes the Windows update files that you do not need after the update; This really surprised me to see how some of those files. are really enormous.
 
CCleaner  link:   https://www.piriform.com/ccleaner/download
 
Glary Utilities link:  http://www.glarysoft.com/
 
WiseCare 360   http://download.cnet.com/Wise-Care-365/3000-18512_4-75744630.html
 
I am using the pro verison of WiseCare as it shows me all the big files on my computer that I really don't need.
 
Hope this helps you.

Hi Lorraine
 
This seems to be an ongoing issue with you and personally I would get professional help from a reliable source, i.e., a recommended and/or reputable PC Technician as I suspect that your issue may be more than just a surfeit of general detritus, etc.
 
If you do decide to try out the suggested utilitles then please make sure that you have a backup of your system and/or data just in case things go awry. These cleaners clean the Registry amongst other areas and as such running several at around the same time can leave your system in a mess (not very likely but can happen).
 
As I have said to you in the past you need to check what the state of the CPU & RAM usgae is on your machine and if high then we need to know what are the top 4 or 5 processes that are consuming it, and from that we may be able to spot something and so make a determination as to cause, etc.
 
Regards, Baldrick