Currently I'm running Raspbian but I'm willing to install any version of Linux. I just need the Pi as a dedicated browser opening one internal site with images. Works great with Midori and Chromium but image transitions are very sluggish.
I have been playing with this and found the best I could get was. firefox for RPi apt-get the following iceweasel (this is the browser) browser-plugin-gnash (this is for some limited vid like youtube)
The few sites I loaded do good vid is pretty bad but at low settings on the quality and some higher settings on the Pi its not to bad. For larger sites it can be a bit sluggish. I was running at pretty much every setting and mem split up to 256. It wont likely stream movies or long winded youtube's, but for checking mail and general surfing it can support much more then the stock browsers.