Yes, Oblivion will play in Windows Vista, I think that's what you are asking.

However, there are some problems. You should play in administrator mods on vista. and, If you want mods,

Quoted from the Oblivion Mods FAQ WIKI

Using VISTA only: If you have downloaded and installed, and the mod is appearing in your Data Files List, but not in your game. Then you should reinstall Oblivion into a different directory instead of the default.

Installing mods on a Windows Vista system is bit trickier than it is on Windows XP due to Vista's increased security.

For best results, it is recommended to install Oblivion to a location other than the default C:\Program Files\ folder. Another location such as C:\Oblivion\ or D:\games\Oblivion\ will work better. This will avoid the file permission problems many users have experienced due to the increased security restrictions Vista places on the Program Files folder.

yea this was my question thx
Wiki entry on installing Oblivion in Vista: http://cs.elderscrolls.com/constwiki/index.php/Windows_Vista

I hope this answers your question.