Welcome Ralf, and I have to say I think you made a great decision going with the Cybook.
When I changed from reading on a Pocket PC to a e-ink screen, I didn't realise how much I appreciated it until I didn't have it any more. I do still read on it and my n800, but nowhere as long as I used to in the past.
And the Dictionary is something which I underestimated when I got the Gen 3, but now can really appreciate the utility.
So Welcome again, and feel free to ask any questions if you get stuck.
And If you enjoy the classics, there is a great collection of Public Domain books which have been superbly formatted for the reader available on this site. Just click on e-books and select Mobipocket.