First off, welcome to the forums. Feel free to ask questions whenever you need during the learning process.
The utility that performs the installation on HDD will eat all resources of your computer. Your CD player is connected through a USB 1.x port and that is very slow with data transfer. Those is the main reasons for being terrible slow. Once you have it installed the running system takes between 100 - 200MB of RAM and is much faster than the Live CD.
Remember current popular webbrowsers are very resource hungry, so as long as Midori can handle the pages you want to visit I would stick with that browser.
Glad Plop helped you out.
- graywizardlinux likes this