Need help on a Legacy setup

[albee1952]

G5 running Leopard(10.5.8) with HD3. Basic stuff is loaded up and working, but many things need downloads and/or updates and Safari, to put it bluntly, is the biggest POS ever in this incarnation. I have been all over the internet for 2 days now in hopes of another browser but cannot find anything that will actually download and install. Of course, since Safari refuses to load any page I need, I have been also searching via my Windows 10 PC(which has no issues downloading .dmg files and has done many so far). Every google search comes up with several options, such as :
tenfoxfour
firefox version 16
Vivaldi
Omniweb
Stainless
but I can't find an actual download for any(found firefox 16.2, but of course, that version will not install on Leopard)
Any ideas will be appreciated