Hi
When i write something basic in the software (e.g counter with led display), and i want to change the script (e.g. Changer the delay), how long does it take to compile the program transfer it to the board and run it?
Matter of 1-3s or does it take more than 15s?
both the compile time and the time to transfer the program to the flash memory in he processor depends on the size of the program.
around 10 s for each of the two steps is probably average. Might take longer.
wow, that long? Guess i'm spoiled from PHP 
Pah, young people today...
When I was a lad, it took 15 minutes just to compile a program, and that was late at night when nobody else was using the computer!
For a large software development project today, compile times from several minutes to a few hours are not uncommon.
Arduino relies on an "out of process" compiler. Arduino IDE has to start a seperate program to compile the program.
The transfer to the Atmega processors flash memory takes place over a slow serial connection.
But remember that once the program is in the flash memory it remains, surviving powercycling the Atmega processor, so it is only if you need to make changes in your program it matters.
since we are on a similar topic, il just ask this here:
besides just uploading the code to the i/o board... which is what i have done since the first day i got the arduino (like 2 weeks ago), wat does it mean to "burn bootloader" using whatever the different choices are?
It almost sounded like you wanted to recompile and upload just to change process values in your application. Normally you would just set up communications via serial port, and the change in process value would now be instant.
The bootloader is the piece of firmware that programs the rest of the microcontroller over the serial port. Without it, you would need special hardware to write new code into the Arduino.
When I was a lad, it took 15 minutes just to compile a program
At the risk of being Pyhtonesque .... Luxury
When I started programming you could submit your punched cards once a day. Imagen learning to program only being able to type RUN once a day and not at weekends.
When I started programming you could summit your punched cards once a day
I remember those days, when the temples for punched card readers where built high on the crests of mountains. 
But I can't edit your quote.
"We programmed in ones and in zeros,
and sometimes we ran out of ones!"
When I started programming you could submit your punched cards once a day. Imagen learning to program only being able to type RUN once a day and not at weekends.
I've often said that my typing skills are so bad, I'd be doing something else for a living if I had to deal with punch cards in school. Fortunately the last punch card machine was gone shortly before I started.
We did have to use line-mode editing, though. Full screen capable terminals were for faculty and staff. (:
-j