The last time I used a form wizard was back with Access 2.0 (before windows 95).
Just tried out the form Wizard in 2007. The last page of the wizard asks for a style. Which one did you pick? Have you tried the Access 2003 style?
Once the wizard creates a form, as far as I know you can modify anything on the design.
a colored rectangle at the top of the detail section, under my fields
If this is in design view, then it sounds like the controls have been grouped.
The Group and Ungroup commands are on the 'Control Layout' 'chunk' of the 'Arrange' tab in form design view. They're a little difficult to find because they are displayed as icons only, without labels. 'Group' is just to the left of 'Snap to Grid' with 'Ungroup' directly below it.