Hi, kath2411 -
Welcome to Apple's Discussions.
First thing to do is to increase the Preferred memory allocation for Internet Explorer - adding 30 or 40 thousand, or even more, to the original Preferred amount is not excessive.
Article #18278 - Assigning More Memory to an Application
Emptying IE's Cache on a regular basis can help, too. To do that, with IE running and the active app, open its Preferences (Edit menu) and go here - Preferences > Web Browser > Advanced. There's a button in the middle of that page to empty the Cache.
If your machine is connected via broadband (cable or DSL), you can also try setting the Cache to zero. IF you do that, it is a good idea to throw away the file IE uses as its cache, here - System Folder >> Preferences >> MS Internet Cache >> IE Cache.waf - (do that with IE not running).
***
I tried loading Opera 9, but it - and most other programs I try to install - say they can't find the application program that created them....
That could indicate the desktop file is overly bloated or corrupt. To fix that, rebuild the desktop file (note that the "desktop file" and the "desktop" have very little to do with each other).
To rebuild the desktop safely, restart - immediately hold down the Shift key until you get the "Extensions Off" message; then release Shift and hold down the Command and Option keys until you get the splash screen asking if you want to rebuild the desktop; click yes (or okay). Once that's done, restart to turn your extensions back on.
That message can also result when the drive is too full. When a drive gets more than about 85% full odd things, strange behaviors, can start happening. The solution for that is to archive off enough stuff to regain adequate free space on the drive.
It would not hurt to boot to your most recent OS 9 Install CD, then run Disk First Aid from the Utilities folder on the CD. Let DFA have a look at the drive, and allow it to repair what it can. It is not unusual for DFA to find things it just can not fix - it then becomes necessary to use a stronger utility, one such as DiskWarrior or TechTool Pro.
***
Also I read there is a pull-down tab for listing new questions with a discussion group. If there is such an item on my computer, it is seemingly invisible. In easily understood English, can someone tell me the proper way I should have listed these questions?
Seems to me you have accomplished that - and in the usual way, except that you added your question to an existing Topic's thread rather than creating a new one of your own.
In Apple Discussions, a new Topic can be created only when you are on a Forum page; one can not be created while on a Category page.
If you look underneath the large Apple Discussions glyph in the upper left of each page, in large grayish type you will see the name of the page - the first word in that name, "Category:" or "Forum:", gives the type of page.
For example, the OS 9 Category page is this one -
http://discussions.apple.com/category.jspa?categoryID=99
If you look in the section in the upper part of that page, you will see two forums listed. If you click the one named Using Mac OS 9 you will be taken to that forun, here -
http://discussions.apple.com/forum.jspa?forumID=669
This thread is in that forum. Once in the Forum, there will be a "Post New Topic" link in the upper left of the page, just under the page's name.
As far as a pull-down menu or tab for questions, I've never seen anything like that in Discussions. Perhaps you could provide a link to where you read that?