I am using MSN explorer.At the top in the bar it states "Type a
Keyword or Web Address. All the way at the right is a checkmark in a
box.When clicked upon it opens as a drop-down box and shows items
previously searched for.Is this unlimited? How does one delete the
items,one no longer wants from that drop-down box? Delete does not do
it.

I don't have MSN Explorer, so I can't verify this, but it appears that
the AutoComplete feature cannot be disabled:

"Go to the MSN explorer's help file, you'll see that:

Disabling AutoComplete

In 'IE' you can clear your AutoComplete history, and you can restrict
AutoComplete to Web addresses, forms, and user names and passwords on
forms, or disable all three. In MSN Explorer it is not possible to
modify or disable AutoComplete."

http://groups.google.com/groups?selm=%23gEPfzC4BHA.2224%40tkmsftngp02&oe=UTF-8&output=gplain

"It is not possible to disable the autocomplete in MSN Explorer/MSN 8"

http://groups.msn.com/msn8forwindowsxp/general.msnw?action=get_message&mview=0&ID_Message=116

Sorry to have more bad news, but here's yet another newsgroup post
that quotes the MSN help file as saying that you can't disable
AutoComplete in MSN Explorer:

http://groups.google.com/groups?selm=%23RhU4svVAHA.143%40cppssbbsa05&oe=UTF-8&output=gplain

I've found some software that might do the trick:

"Privacy Eraser is an internet eraser that protects your privacy by
cleaning up all the Internet history tracks and past computer
activities. With simply one click, Privacy Eraser allows you to erase
the cache, cookies, history, visited/typed URLs, autocomplete forms
data, saved password, index.dat files of your browser, and Window's
swap file, temp folders, run history, search history, open/save
history, recent documents and more. The cookie cleaning feature allows
you to specify cookies to keep, so that you don't erase your important
login cookies. In addition, you can change the paths of several system
folders (Cache, Cookies, History, Favorites etc.) and customize the
Internet Explorer (IE) title bar text. With Privacy Eraser Pro's free
plug-ins, you can easily erase the tracks of popular programs. We
currently offer more than 150 FREE plug-ins which supports the most
popular programs such as ACDSee, Acrobat, Microsoft Office, KaZaA, MSN
Messenger, Real/RealOne Player, Media Player and many others. Our
internet eraser also support popular browsers such as IE, Netscape,
AOL, Opera and MSN Explorer."

http://www.privacyeraser.com/

This software is not free, but I might be able to find something
similar that is shareware or freeware, or a free trial. Let me know if
this sort of thing interests you as a solution to your problem.