Yes, but you run the risk of really killing your PC. The process involves reflashing your BIOS with the image that you want. You'll need to find out what BIOS you have and do some research on how to flash it and how to insert a picture into the flash binary. WARNING : If the flash doesn't work, your PC won't work and it's a right royal pain to flash it back to its original state.
When we bought our new HP PC, we had a similar greeting. I went to settings to change it without any problems. But I am talking desk top background - are you?