opera 10 beta is new look and boosted performance.Opera 10 enables Turbo technology.With the help of Turbo Mode,it can Speed up your web browsing.Also it look very nice.
I had installed opera 10 in windows 7.It runs fine.I think that it supports windows 7.But its speed is more slowed than opera 9.And can't open some website.
If you upgraded to Windows 7 from Vista and want to download Opera 10 with Turbo-enhanced release for Windows,please check out the page.
You might also try to install as Administrator