Well thanks for all the info.
I'll now read all what they have to say on their pages.
And I'll now think how will I orginize that. and so on.

I have get lot's of usefull informations.
Well I dont know will I give open code. Probably I will. But I'll see. That will append much how shall I make that.
But I dont want break out from standard like MySQL (as I know most of servers have that) so probably I'll go with that. Now will it be C++ with QT or C#. That I'll see for what I have libraries that have better integrasion into compiler (more VS versions and in what oether free compilers).

Only one thing is for sure it will be MySQL or MS Access database.
All computers are on WinXP so it can be MS Access database but heh MySQL is most wided.