Install uClinux-dist-test with patches for nios2 under /root dir. UClinuxDist
NOTE, the gentoo image does not contain Xserver and much tools. You will need to use "emerge" to add more packages.
Or you can use other image,
albertyong88 said, You can download blackfin-colinux (from blackfin uclinux wiki site), which is very easy to install. It has most tools you need. It also provides Xserver and stuff ...
You can then follow the wiki for installing Eclipse as your development platform if you are not confortable on using command text editor.
bigboss25 said, Or try using Colonist (http://colonist.sourceforge.net/) with Kubuntu Live image, which include KDE UI and some apps (OpenOffice, text editor ...). I use Xming as X server to display KDE desktop on my Windows desktop. Currently, it works well but is a bit slow.
Note that during install , Colonist will also create virtual drive for your Windows partitions, so you will be able from KDE to see all your windows drive ;o)
Configuring Xming X server is a bit tricky (it appears that your firewall must be disabled), but it works.