Better hold down the shift key while pressing reset as if the weird colours are there immediatly, it may be applying a RGB tone curve or calibration alteration on import. Holding shift will reset to adobe zero's.
If that works go from the menu - Develop: Set Default Settings: Reset to Adobe settings.
Try turning Calibration, Tone curve and HSL off one at a time also. Last potential remedy I can think of is to make sure you havn't got an "alien" ICC profile turned on in Soft proofing.