Your decision to circumcise or not is usually based on family preference. This does not need to be a scientific decision. Your personal preference is a reasonable way to make a decision. There is a very small potential risk of medical problems if your son is not circumcised. Most issues are related to the risk of infection due to the foreskin being in place and cleaning of the glans of the penis being more difficult. Most parents decide on circumcision.
If he is not circumcised then leave the foreskin alone. Do not retract it and it will retract naturally as he enters his early school age years. You may notice a small amount of white putty like discharge from the tip of the foreskin. This is a natural lubricant. It does not signal an infection. If he is circumcised you need to lubricate the glans of the penis with Vaseline every time he is changed. This will help protect the unprotected glans from adhering to the diaper and also makes cleaning the area much easier. Vaseline should be applied by
squeezing it out of a tube as you move the tube around the shaft of the penis. Do this every time the diaper is changed. After about 1 week the skin will change from a shiny red to a dull grey and the healing is complete. If a bell system is used the guard will fall off the penis after about 1 week. It can be discarded.
If you child is circumcised the foreskin usually reattaches to the glans. You may also see some small white natural lubricant along the edge of the foreskin. This is natural. In the past many people would retract the foreskin daily to prevent adhesions from forming. This can be done but is not necessary. The foreskin will release from the glans by early school age years. If you do retract it then you will need to clean under it daily. This is extra work so leave it alone.
To prevent diaper rashes the best treatment is prevention. Use Vaseline on the entire diaper area every time you change your child. This makes cleaning easier and prevents diaper rash. Make the diaper area look like your child is about to swim the English Channel. You can never use too much Vaseline. By using Vaseline there is a barrier between the skin and the urine and stool which can irritate the skin. It also serves as a lubricant to prevent friction and irritation from the paper diapers.