Question: Everytime when I want to install the ubuntu, it calls me to download the ubuntu-12.04-wubi-amd64.tar.xz! Because of my poor network, it makes me crazy! How can I install the ubuntu 12.04 without downloading ubuntu-12.04-wubi-amd64.tar.xz?

Answer: 
If your network is really slow you might want to order one of the [Ubuntu CDs/DVDs](http://shop.canonical.com/index.php?cPath=17). You could also ask someone to download and burn the [DVD images](http://cdimage.ubuntu.com/dvd/current/) for you. There is also a mini-iso that has a "network installation" option which tends to download a little bit less. That one still downloads quiet a lot of data and is hard to get by as it is not an official option any more (as far as I know).
Your best answer is to get the live-DVD. Please use this to boot and use the 'Try Ubuntu' option to make sure it runs OK on your hardware before attempting to install. You then have the option of using wubi recommended only if you use Ubuntu only occasionally or installing on a partition. Either way, make sure you can recover all data and the Windows operating system if something goes wrong.