Q: Safari 7.0.6

You are right you need to get the latest version of Safari on your Mac Get the latest version of Safari for your Mac - Apple Support

What happens *exactly* when you visit http://www.apple.com/fr/ ??

screenshots tell us a lot

I can change "User Agents" in Firefox to "tell" a website (this case, http://www.apple.com/fr/) that I am using Safari 7.0.537.78 (OS X Mavericks 10.9.5) - it displays as expected

Are you having problems with any other websites?

Safari/Preferences/Advanced - enable the Develop menu, then go there and Empty Caches. Quit/reopen Safari and test. Then try Safari/History/Show History and delete all history items.  Quit/reopen Safari and test. You can also try try Safari/Reset Safari. The down side is it clears all cookies. Doing this may cause some sites to no longer recognize your computer as one that has visited the web site. In Finder hold down the option/alt key while selecting the Go menu item. Select Library. Then Library./Caches/com.apple.Safari/Cache.db and move it to the trash.

Go to Safari Preferences/Extensions and turn all extensions off. Test. If okay, turn the extensions on one by one until you figure out what extension is causing the problem.

Safari Corruption       See post by Linc Davis