sql server maintence plans. What account to use?
Since the jobs will run as your SQL Server Agent account, that's the way to go: http://msdn.microsoft.com/en-us/library/ms187658.aspx

It is a best practice to run your SQL Server engine and your Agent under different accounts however, the logic being if one account is locked or otherwise compromised, you aren't hurting the other. To change your Agent account: http://msdn.microsoft.com/en-us/library/ms191543.aspx