Eliza,
You don't give us much to work with regards how you've made your removal or installation attempts. But if I had to guess, I'd suspect you've a hardware issue in the mix...
What operating system and hardware (CPU, Graphics, RAM)?
Do you have administrators group access for your system?
Have you run a disk diagnostic for your HDD?
If using a DVD, have you run a diagnostic of the DVD reader?
Did you verify the HASH value of the installation packages?
Are you mounting a copy of the installer ISOs as a virtual disk? Is it a file local to the HDD?
Are you attempting the install from a network share?
Let us know, we may be able to help.
Stuart