system recovery unknown password

[Agent_Smith11]

I dropped somthing hard on my Gateway laptop,it will turn on but once @ the desktop the cursor moves around but it won't allow me to acess anything. Itried to do a system recovery but it asks 4 a password @ the recovery login admin I've never had one to my knowledge because i never made one. I bought the laptop as a display unit of the shelf. it has windows vista o/s. are there default passwords i can use? I use this laptop for work so its real important to me.