The simplest way is to wait. Yup, it can get annoying but if the files you're talking about are that rare then you should expect them to be stuck there for some time (if you're unlucky).
Always remember: the more sources available (for the same file), then the faster the download (in general).
If you found, like, a file that's only available by one person on a Modem connection and with only one to two stars (worst case scenario, ok?) then when you double click the file to download, be sure you know what you're getting yourself into. Don't expect it anytime soon, especially since the uploader can at all times disconnect for any number of reasons and/or get too busy and Queue you download 'cause he's uploading his rare files to too many people.

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iMac G4 OSX 10.3.9
RAM 256MB
LW 4.10.5 Basic
ADSL anything from 3 to 8Mbps/around 1024kbps

"Raise your can of Beer on high
And seal your fate forever
Our best years have passed us by
The Golden Age Of Leather"
-Blue Öyster Cult-