Arduino reset

Hi, i have two problem with arduino duemilanove

1) when i press serial monitor arduino resets, even when i not write serial.begin on software.

2) on arduino start the loop led flashes 4-5 times after that he start, this happens only when i connect arduino at pc, if i connect arduino on 220v> usb he start immediately

why?

when i press serial monitor arduino resets, even when i not write serial.begin on software.

Yes that's how it works.

on arduino start the loop led flashes 4-5 times after that he start,

Yes that is how it works, it is looking to see if a program is to be downloaded, if not it continues. The LEDs are controlled by the PC not the arduino.

Ok and why when i close serial monitor he continue to send data for 4-5 times?

When you close the serial monitor you also reset the arduino.