Hi,
I have an HP Pavilion dv9999 notebook running Windows Vista 64-bit edition. Now I want to set Linux and make the notebook dual-boot OS system.
My questions is which Linux is the best to work with HP Pavilion notebook? Which Linux can support all the hardware devices such as wireless, video, sound and WebCam on this type of system.
Thank you in advance!
I don't have facts but from my personal experience, Ubuntu seems to have the most hardware compatibility...for example, a friend of mine installed Ubuntu and immediately plugged in his USB dongle provided to him by his ISP for internet connectivity and Ubuntu brought up an interface for the dongle that allowed him to choose who the ISP was and this interface contained a list of all the ISP's in Sri Lanka.
I've never had too many problems putting Ubuntu on laptops either. Most of the time, there will at least be a third party driver for even the most exotic hardware out there.
The best thing for you to do is, get Ubuntu and maybe Fedora and some other Linux distros's Live CD's and try them out so that you give the distro's a test run before committing to them by installing them.
Thanks a lot for the info. 
SuSE is the one I hope to use if possible. I prefer to install an enterprise version, either SuSE or RedHat. Ubuntu is good for desktop, right?
How about the dual-boot configuration? I have't done it for a long time. Today Linux must live together with Windows very well I guess.
No problem.
Why SuSE? I was about to suggest SuSE too but I can't say I'm a huge fan of the direction Novell has taken over the last 2-3 years but to each his own 
And RedHat Enterprise Linux is more tailored for a server environment though it will still function well as a Desktop. But Ubuntu, in my opinion, is by far the best for a desktop distro even surpassing SuSE.
The main issue with dual booting is having a boot loader that understands what's going on with your MBR.
If you install Ubuntu on a PC that has Windows already on it, Ubuntu will configure GRUB for you so that you don't even have to mess with the GRUB config files.
If you want to install Windows on a PC that contains a Linux, you will probably have to edit some grub config files since the MS boot loader will no doubt overwrite the MBR without concern for any other boot loader that should be allowed to exist since this should ultimately be your choice.
see: Ubuntu: Dual boot with Windows
NOTE: Current Ubuntu version is 8.10. The next Ubuntu release comes out in 4 days (April 23rd, 2009) and it will be version 9.04. If I were you, I would go with 8.10 and wait for about 2 months and THEN install 9.04 along with updates and patches to ensure your system is bug free.
The reason I want to use SuSE is that our company has some systems using it. RH Enterprise is fine too. If Ubuntu is only good for desktop, I prefer not to use it since I want to focus on hands-on practices of system admin. RH is not free now. I only have RH Enterprise version 9, that probably won't support my notebook well. I will have to find updated drivers for hardware devices.
Windows Vista is installed. Dual boot should not be a big problem. Thanks!