I noeticed ggoogle gorups has the new interface and you can´t get the old one or is it possible? thanks

Hmm. It looks as though they're switching back and forth. Just recently they introduced the new one and replaced the main one. Then they put the old one back in place. Now the new one again...
I don't think there's a way to bring back the old one.
Unless maybe you go to the German Google Groups, or other non-US versions...
http://groups.google.de

it's back to the old version again.

lumitra
[...]

I still get the new version...