Installing hdd

Hi There, first of all i would like to mention that i have some basic ideas about PC hardware . However I have to mount a new HDD to my PC but i already had 2 HDD's , The one i boot had 2 partitions which is "SAMSUNG HD161HJ" the other one alone "ST3200822A". mobo is gigabyte EP45DS3R

My goal is after installing a new HDD "SAMSUNG SpinPoint F1 HD103UJ, 7200rpm, 32MB, 1000GB, SATA-II" to keep only this drive on my PC and completely remove the others. Since I do not want to lose the data in older HDD's I have created the following scenario. I need your advices .

1-I will keep boot drive and remove the other and mount a new HDD
2-All the data on boot drive will be transferred to to new HDD -which will have 3 partitions and one will be dedicated for OS.
3-I will remove the old HDD then OS will be installed to first partition of new HDD and my other old drive be mounted and removed soon after all the data copied to new HD.

Your advices and opinions will be appreciated as I might be wrong due lack of knowledge . Thanks in advance.

Why not this way? Install you OS first to the new one (Take note: Unplugged the 2 old HDD first to avoid formatting the wrong HDD...) Make the settings complete.

After that, return the 2 old HDD. You can do this one at a time... There, you can copy your back ups... (Just recognize the name of HDD in the BIOS for Boot Priority. It should be your new HDD in the 1st position...)

Thanks for your message. I dont want to use old 2 HDD coz their capacities are neglectable since new one has got 1TB . On the other hand new HDD sata 2 others are not .