If you have Outlook Express (OE) running and find you can not delete your emails anymore chances are your mail box dbx file is corrupt or just too big.   Outlook does not by default enable empty deleted email or sent email folders.  These files can become huge over time and tend to become corrupt.  A temp work around is to try the Shift and DEL at the same time while the message is selected (not open).   This bypasses the use of the deleted mail folder.   These folders that everyone refers to are actualy hidden files on your hard drive.  Rather than doing all the steps to make explorer see where the files are here is an alternate method.
1st  Make a backup of the email you wish to keep.   Create a new folder in the root folder of OE,  just above the Inbox.  Move or Copy (prefer copy) all the email to your new folder.
2nd  Open up Explorer and make a new folder in your choice of location.  IE C:\mymailbox
3rd  From the Options menu in OE, locate the Maintenance Tab.  Select change mail folder, browse to where you created the folder and click OK.  You will get a prompt saying to need restart OE.  Restart OE.
4th  After the files move over, close OE.  Now go to the new folder you created in Explorer and look for the files with the same name as your folders from OE.  Inbox.dbx  Send.dbx etc.  Make sure the new folder name you created has a file with that name.  Remove all the other files except the one you created.  There should be nothing there you need and the files will be recreated on the start up of OE.  If you are nervous about it, move the files to a different folder instead of deleting them.
5th  Start OE.  OE should be running normal now and all the emails you could not delete should be gone.   Move your emails back to the Inbox folder if you like. 
Just to note when I had this problem the mail files were huge, 2GB and 800MB.  Remember to empty out the old mail once in a while.

With the introduction of Internet Explorer 7, MicroSoft included a search bar.  It was nice of MS to offer a search bar that even allows more options than MSN for searching but they didn’t include a simple option of enable or disable it.   You would think there would be a simple right click to enable and disable just like all the other toolbar entries.  There is a simple entry to add to the registry remove it from the toolbar.   The entry below will remove the search bar for the current user, not forcing anyone else who logs on your PC with the same setting.   If you wanted it set across all the users then change the root path to HKLM instead of HKCU.  Changing the 1 to a 0 will reverse the setting.  Restart IE7 for the changes to take effect. 

[HKEY_CURRENT_USER\Software\Policies\Microsoft\Internet Explorer\Infodelivery\Restrictions]
"NoSearchBox"=dword:00000001