Is this board new? This is common for a dead CMOS battery... Press F1 to enter setup (aka the BIOS) and set the time and date. If you ever see this error again...2 more quick beeps
Two Beeps: POST/CMOS Error
then you need a new CMOS battery which is located on your motherboard... it looks like this HERE and is very easy to replace.
CMOS date/time not set
Since it appears you will get to the BIOS, start plugging one thing in at a time and powering on each time, if you haven't done this already, to find the culprit of your original problem. If you don't find a problem, don't worry about it.
Next, set the boot priority in the BIOS to CD ROM first and Hard Drive second, and insert your Windows Disc. Press F10 to save and exit the BIOS, your computer will reboot and start the install of Windows.
THIS RECENT POST BY ME may be some help to you, read all of it.