The main reasons for general slowness (you don't give any understandable example of specific slowness) are:
1. Not enough RAM for all the programs you run.
2. Hard disk VERY full (that is, more than 98%).
3. Running too many programs, especially malware.
4. Hard disk switch from DMA to PIO mode.
The 2 things I can say:
1. Updating Java is only done for security reasons, not for performance reason. The 2 reasons for that: (a) a new version only contains security patches, and (2) you hardly ever run Java.
2. If you do a system recovery back to factory conditions (how to do that depends on your PC, there is no general recipe) it will be as fast as it was when you bought it new.
Kees
i cant figure it out my computer is slow i think it takes a 5 to 6 sec delay with windows i recently switched over to the internet explorer 9 and i recently noticing there r alot of files in the memory dump when i go to disk cleaner do i need to update java?.games r terrible to play..very slow

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