What's going on? Download, then wait busy, then download, then wait busy ...
 

I'm running LW 3.5.8 on P2-350 / Win98 with 128M memory, and a cable internet connection. Recently, I have begun to attempt to download some half-hour TV show episodes. It's taking days! What happens is, I get a four star result in the search, start downloading from it, and for a while, everything is great; I'm downloading anywhere from 10 to 25K per second. But after the first few minutes, the DL rate starts getting slower and slower, eventually reaching 0K. Then the status changes to "Waiting n seconds for x busy." At the end of the countdown, it starts downloading again, but only for three or four seconds. Then it's back to another minute's waiting. Then three or four seconds of downloading, followed by another minute's wait. And so on. And so on. And so on.

WTF is going on? I've got no other apps running and uploads are restricted to 25% of my bandwidth.

Sounds like if your problem is just with a single file, then quite simply you have a bad uploader.

The uploader is unable to maintain a stable transfer connection with you for very long, and thus the seemingly stable connection decays and is eventually dropped.

There's not really anything you can do about that except find another source.