...molasses in January.

Everything is running v-e-r-y slowly. I get a lot of the whirly rainbow icon when opening just abot anything. I think probably I need to do some cleaning up of files but I am petrified of trashing something important since I am one of those "knows just enough to get in trouble" types. Is there a reliable - and understandable - clean-up program available for 10.3? I really need something that will literally walk me through a clean-up and tell me what it is doing in a comprehensible fashion. I know that some of the slowness is due to my satellite connection when I am online but even pulling up local folders causes it to stop and "think" for up to 15 seconds, sometimes longer.

Sounds like something is running in the background. You can start by doing disk permissions: finder>applications>utilities>disk utility. Do the verify then the repair. You can also use onyx:

Titanium Software

Just stick to the two tabs at the top of onyx that say maintenance and cleaning. The gear and the broom.

If that doesn't work, post back and I'm sure someone will continue to help you. And out of the blue, have you thought about/able to upgrading to tiger? Much faster OS and more stable than Panther.