had the same issue with my laptop. it’s your nVidia card. main KDE desktop driver does not work with it.(have exactly the same chipset on my laptop. I think my is G6153)
not sure what will be the best way for you, but I simply did install using LXDE desktop.
it works with nuveu driver (not sure what the proper name but it is a default driver supplied)
after you install, you can setup the proper nVidia driver and install full KDE desktop if you like.
You need the G02 driver, i.e. the one labelled “For GeForce 6 and GeForce 7” on that page.
You should be able to install it in “Recovery Mode”, afterwards reboot and the normal boot/login should be fine as well.