BD - I use Outlook 97 and neither of your problems occur. The PP issue might be dealt with by correctly associating .ppt files with the PP app., which you do by going into Tools, Folder Options, File Types from Explorer (not IE, but the files mgt Explorer).
Go into Tools, Options in Outlook to solve the mail read problem, or Right click on the item and select, Mark as read.
Outlook 97 does not auto complete addresses, period. Thunderbird does.