Are those hard freezes needing a hard reset (hard freeze)? Or intermitent freezes rendering your computer, or an application, unresponsive for some time, but that eventualy unfreeze itself or require you to kill a single process (soft or intermitent freezes)?
Some causes of hard freezes:
Many, possibly most, freezings can be caused by bad drivers. Try updating your video drivers and maybe your audio drivers.
Overly agressives BIOS settings:
Check the BIOS settings. Make sure that the RAM timing is set to the nominal settings (as SPD).
Set the CPU at it's nominal speed if it's overclocked.
Some faulty RAM may be at cause. Find and run a memory test application. You normaly need to boot from an alternative media, like a USB key, to have an effective test. A test that run in Windows can't test the memory used by the OS.
If that test report failling RAM, you need to replace the faulty component. A good test utility should report what RAM stick is going bad.
It can be some other hardware fault.
On older computers, overheating can cause crashes and freezes. Remove any dust that is accumulating on the CPU's heat sink. Use a can of compressed air to blow the dust away.
If the video card have it's own fan and heat sink, then you need to dust it off as well.
A failing video card is possible. If that's the case, you need to replace it.
Worst case: A failing CPU or some part of the motherboard are dying.
In this case, your only option is to replace the computer.
End of hard cases.
Another cause can be conflicting applications, accessories and add ons. (mostly soft freezes)
In Internet explorer, disable all additional tool bars. Many are badly coded and can cause hard crashes. Anyway, most are effectively useless or redundent with the basic tool bars and the actual menu.
Disable some startup items, starting with any and all so called 'quick starter".
What kind of stuff are you cleaning?
The internet cache (temporary internet files)? You don't realy need to do that regularly, but you can reduce it's maximum volume and shorten it's retention time. A good dimention can range from 50 Mb to 200 Mb, and a retention time of about 1 week should be enough.
If you have more than a single drive, tou can move it to another drive.
Most internet stuff that does accumulate are user downloaded files.
If there is another person using your computer, then that person may download a LOT of stuff. A good discution with the other user may be of use.
Electro
February 2012