If you want to install Linux in your PC then unpartition some space for that then boot it using Linux installation CD and install but if your Linux didn't found your hard disk then use this command at the time of installation.
linux pci=nommconf all-generic-ide
For a beginner, I would recommend Ubuntu + Google Search! Ubuntu has great community support! And trust me when i say this, you will need some good support.
Installing linux is actually the easiest part. Setting up and customizing and installing various programs is the harder part.
To install linux just download a iso copy of any standard linux distro like Debian, Fedora, Ubuntu, openSUSE etc. and burn it to a cd/dvd using and iso burner (google search to find a decent iso burner) You can also install linux from a usb flash drive! You'll need unetbootin + 1GB (minimum) Usb flash drive + a copy of linux distro.