Which Edition from shop do i need
its only for me,i may install it on both of my pc's with a network to speed things up.

Such as.
Both pcs are linked by wired network and are both in front of me.
I use one to program etc and the other to run the game

I dont see home edition on the web site?

YOu don´t need a home edition. Conitec produce 4 versions with different features per edition. For example pro has all features plus render2texture, full physic, shaders. The com has shaders and 1 limited physic and all others, extra has nothing from them, only standard features. You have to know what features you need. You can work with else edition at home for hobby or professional at work. Like you want.

ok Really all i need is it to be great at 3d worlds only.
Im that intrusted in createing a game but instead creating and viewing 3d land scapes etc.
So i guess its got to have good shaders

Best bet to start real development is the commercial edition. If you'll find later that you need some more (mirrors, wrs, built-in unlimited physic, etc.) you may upgrade to pro.

yeah, you should test dthe program with the 30-day-trial and lern how to use it. if you buy the com at first, you´ll save money (upgrade from lower editions is more expensive then buy it direct).
and with the com you have many more useful features like network-support

ok ill be testing for 30 days once my new pc is all set up again
then ill probley buy commercial edition
after i get to a stage when i decide to update ill go pro,but also by then version 7 maybe out

If you buy now A6 you get A7 for free, as far as i am concerned.

is this necessary for boughts 2 years ago?
i hope but i dont think so

No, only for Versions that were bought after a certain date in 2007.

A7 commercial will have unlimited physics so that's one pro-only feature that is trickling down. Of course BSP is trickling up to pro-only, but it's a different flavor of bsp and will work [eventually] with concave blocks.