Does www.marketwatch.com work for you with Opera Mini?
I cannot open it with Opera Mini, it says transcoder timeout for me. It's not a new development, I tried it a while ago and I could not access it with Opera Mini then either.
Could you try it if it works for you? It's quite a well known site, so I'd be surprised if it were completely inaccessible with Opera Mini.
Change Data Savings mode from 'Opera Mini' to 'Opera Turbo'