Audi A2 1.4 Petrol All Warning Lights On

I Have Recently Had A Problem With My Girlfriend A2 I Was Driving Home And I Noticed All My Warning Lights Had Come On (abs,both Airbags, Engine Management, Radio Went Off, Lights Went Dull, Wipers Moving Very Slow, And My Steering Went Heavy) I Parked Up And Turned Off Engine And When I Tried To Start Engine Just About Started As If Battery Was Nearly Dead I Put A New Battery On About 5 Days Before As Car Had Been Layed Up For A While And Couldnt Get Any Life Back Into Battery I Was Thinking Is It An Alterator Problem But When I Jump Started Car With Old Battery I Never Got Any Of These Problems Any Idea What It Could Be, Darren