Simple photo editing of old pics

I need 75 old odd shaped photos that Ive scanned in to be centred, turned etc and some of the need increasing in size to no more than 6" x 4". A few of the photos need reducing in size. This needs to be done without losing too much quality given that they are non-digital and fairly old.
These pictures are needed for me to upload to make a digital photo book. I need the task completed to my satisfaction in one week.