Booting (booting up) in computing is the process of starting the Operating System when the computer is switched on. A boot sequence is the initial set of operations performed when the computer is switched on. Some very popularly used bootloaders are GRUB, BOOTMGR, Syslinux, LILO, NTLDR. Linux booting process is much simple to understand and much things to recognize.
The setup process was relatively smooth. Basically, you install Parallels when you would any other software. Then, Parallels walks you through the Windows design and installation. Then, you may also install your Windows applications, like 'microsoft office'. Now you're running a Windows virtual machine with regards to your Mac!
(3) You can install an array of 32 or 64-bit os's as guest operating systems, so you are not just limited to Windows. Currently, I have Windows XP, Windows 7 Release Candidate 1, and Ubuntu Linux.