Deleting search information

I do quite a bit of searching. The names that I search remain in the
individual sites, and also on my main browser. When I go to these sites to
search, all of these names that I searched before come up. This is annoying.
On my old XP, I would be able to just hit the delete button, and they would
all dissapear. This doesn't happen with Vista.
Is there a way to delete these saved names, etc without much trouble?
Please help . . this is very distracting when I go to a site, and enter a
name, and all the names that I ever saved come up. It's distracting.
Thanx . .
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debarybabs