My wife's Asus netbook runs very well on their Linux operating system, and her Hewlett Packard laptop performs nicely with Ubuntu desktop. She has been looking for an alternative to Ubuntu - an operating system that is developed a little more carefully, with fewer "bells and whistles" and more solid computing.
After trying quite a few distributions, she has settled on Linux Mint - an off-shoot of Ubuntu, modified for users who prefer a reliable, no-nonsense, full service operating system.
http://www.linuxmint.com/And it runs the Hewlett Packard flawlessly (with the exception of the no-name camera built in - Linux will normally operate a quality web-cam).
As far as I can tell, Linux Mint would be a good choice for someone looking to replace their Windows operating system with a general-purpose Linux system.