golinux wrote:how do I install Mint on sda1 without destroying Ubuntu on sda2 and sda3?
As mentioned, you'll need manual partitioning. I recommend burning a gparted livecd and booting with it to do all of your partition fun.
I do NOT NOT NOT NOT NOT NOT NOT recommend using a single 115gb partition for Mint. You're stabbing yourself in the back, shooting yourself in the foot, and whacking off your nose to spite your face all at once. Its ugly. Please don't do ugly. I assure you that you'll regret it.