How do you stop google remembering your search history?

and delete all previous search history.

At the right hand side of the google search bar is an arrow pointing downwards. Click on this and the box will expand. You should then be able to see a list of all your searches. In the bottom of the box it says Clear Search History. Just click this and, hey presto, search history gone.
You can also download a programme like CCleaner which will clean up all your unwanted files and speed up your computer. Good luck.

Ctrl + shift + delete

you turn off autocomplete under tools internet options content

Go to tools (should be near the top of your screen when you open an internet explorer page) then click delete browsing history.

Just highlight the history,and press the delete key

go with manu's option, I just did it and it worked.

Click tools, and go to Internet options. Select the content tab, and where it says autocomplete, click settings. In here, clear the forms box.
To delete history, click tools, and then click delete browsing history. You can now choose to delete separate categories, such as cookies or history, or at the bottom you can delete them all. You can also access this menu by going to tools, Internet options, and then where it says browsing history, select delete.

Press Tools
Then: Delete Browsing History

go to tools ( in the top right hand corner of your screen if you have vista)
click delete browsing history
then click
delete cookies
when that is done
click
delete history
hope i helped
=]