Well, there is a lot that has to go right for one to get on the net with a healthy machine, you've obviously been through a lot, so here are my tuppence:

First of all, if your hard drives are new, they are probably not the problem. Hard drives can go bad, but usually they go physically bad and you can't get the system to come up let alone get on the internet. Malware may be active viruses, virii?, but also can be exceptionally irritating ad-ware and spyware, which can slow you down but don't actually try to corrupt your machine, just you. A very basic first step even before anti-virus software is to hook up your broadband connection to a router, then hook your machine to the router. I've lasted for months with no anti-virus software, conservative habits such as not opening attachments, and been very happy (or lucky). If you're going to use anti-virus software, pick one and use it, don't install multiple bits of code that are all trying to do the same thing.

If you're going to the trouble of wiping disks and reinstalling software, and you're still using Windows, abandon 98 and go to XP or preferably XP Pro. You mention you had a disk with Windows 2000 which would have been eminently preferable to 98SE.

If you are ready to toss your HD and it still makes turning noises, send it to me. I'll use it for a linux box I'm planning (my third or fourth).

Anyhow, good luck and hope you find a satisfying link to all that is good on the 'net, of which there is plenty.

Robo