That model came with a small memory by today's standards: 128 or 256 MB. Did you upgrade and, if so, to how much? That's obviously a vital question. Tell me what you've got and I'll tell you what will run (out of the 112 distros I know!) I think you have motherboard graphics, but if you have an added graphics card that will improve things: otherwise some of the RAM is grabbed for graphics.
Does Puppy have Gparted by default? If not, you can download it and examine your disk, and reformat if necessary. Actually, most distros will do that with their installer.
Yahoo is a problem for older computers. This one is comparable to yours, but with 1MB RAM, and I find Yahoo's become unusable, even with Opera. I ended by finding alternatives to the Yahoo groups I belonged to (mostly better, in the event), and quitting Yahoo for good.