Without a model number we can't tell if your HP is compatible. Unless it's really old chances are it can be installed (if in working order)
You can go to the HP website and select your model number and check for Vista drivers and software. If you don't have the manual for the printer for instalation instructions, you may be able to download a manual as well.
Read and follow the instalation instructions.
Any modern printer should be compatible with Vista, just look on the box to see which os is supported.