Outlook 2007 and earlier versions display the Outlook Today page when you first start up, but for most people it’s a fairly useless page since you just want to get to your email anyway.
You can disable Outlook Today easily, or you can use the advanced options to choose a particular folder to start in. You can start by just clicking on the Customize Outlook Today button.
Then just uncheck the “When starting, go directly to Outlook Today” checkbox, which should set the Inbox as the default startup folder.
If it doesn’t, or if you want to make outlook display a different folder on startup, open Outlook Options, click on the Other tab, and then click on Advanced Options.
In this dialog, you can click the Browse button and choose a different folder if you want. You can even choose Search Folders in Outlook 2007, which can be very useful…
For instance, you could choose the Followup Today search folder to only see items that you’ve flagged to follow up with on the current day. Quite useful!