On R5 live cd.
Intel core2 duo Q6600 2.40 Ghz
2 sata hd (non-raid)
4G ram
ATI radeon HD5670
wireless usb mouse
hardwire ps2 keys
hardwire internet
Apparently you have a good sized hard drive? I would just partition the hard drive into 2 parts, one for each operating system. When you install the first operating system just use a piece, whatever size you think you need, of the total hard drive. The installer should have all the tools (probably gparted) to do the partition. Don't worry about the unused part. You can format it after the install. Choose the MBR for the boot. The only time booting can be a real problem is when one of the systems is windows. I don't remember what is on the Watt installation disk for sound control. With any LXDE system, I have always had to install pavucontrol after the install to get a control. Mate-media also works. Here is a general beginners guide for LXDE systems and Linux: http://lxlinux.com