Chromium is Chrome but with some Google features removed. I would suggest that if you can't run Chrome by itself. If you want, try the developer channels of Chrome since 64 bit was introduced and it might help you.
Waterfox is a 64 bit version of Firefox which runs a lot better than the standard Firefox from personal experience.
Safari is one step above IE11 so take that as you'd like.
Midori is also lightweight but crashes on some Windows distributions.
If you haven't already, clear out the cache and such in your browser. Remove any extensions which are just fluff. I did that with my Chrome since it was eating my page file up and now it's working without hitches.