You can change any setting you like in Manual mode. Also, the cameramanual lists settings for variousmodes and what can and cannot be changed. Most modes are preset depending on the outcome you desire. Manual modedoes take some time and patience. Taking action shots with manual mode however, would be a challenge.
Also aperture mode let's you set the aperture and the camera setsd the shuuter sopeedd, so you have no control over the shiutter speed in that mode. Shutter mode lets you control the shutter speed, but the camera selects the aperture setting.