Yep dual boot is what your looking for. You could dual boot but the major disadvantage is like I said setting thing up on an existing HDD with data you don't want to loose. You can use gparted to resize/repartition your HDD and install ubuntu then use grub to dual boot.
Yes linuxcoin is a OS I've designed for bitcoin. it's debian based and contains everything needed to buy / sell / trade / mine and just about anything else you can do with bitcoin. It's security has been beefed up to keep your coins safe and it boots from a USB flash drive. You won't need to partition your drives just plug the USB stick into any computer and linuxcoin will load with your wallet and when you shutdown it's like it you was never there.
Well i'm running windows on a net surfing computer, so I was going to buy a new laptop just for this. They are relatively cheap at about $250. I would not lose any data because the computer is new.
Am I to understand I could download the linuxcoin after I have ubuntu installed, and use that alongside, for extra safety? Or are you implying I don't need ubuntu at all? I'm just not experienced in programming, so the easiest route for me is the best, but I want safety overall. I'm thinking if I have ubuntu installed, then running linuxcoin might be easier. Am I mistaken? And thanks for taking the time to help out, drgr33n.