Thanks for the link but it is in C++ code again and that is confusing for me (pointer things and such). Isn't there a good pascal example? (I am looking for that for over a week already, so therefore I posted it here, since all those C++ example aint doing it for me).
Just get used to it. You won't get far if you only want to read pascal-tutorials because there aren't many. Moreover, there is almost no difference between pascal and C++ in that example, because it's just a few function calls. Just look at the global flow of the program and look up the documentation for each function and read it carefully. Also, browse these forums because I think there are more people who had problems with VBO's.

PBO's are totally different and I have not used them much. My guess would be that it's not the fastest way to draw lines.

The last parameter of glVertexPointer() is the offset into the given vertex array. If you want to use your entire vertex array, just set this to zero. That was all covered in the link I gave you. The only way to know how to use functions is read the documentation. I'm not going to do that for you.

Good luck!