I have just gotten a Leatherwood Hi-Lux 30mm red dot site, for no good reason really I am am just a weekend plinker. I have noticed several mounting configurations with non-mag red dot sights. My question, is it best to use in conjunction with iron sites (mounted in front of carry handle) or use alone)on top of carry handle. any input is greatly appreciated

Opinions abound on ARF.  With the right information you can make your own decisions.

If I understand you correctly, you have a 30mm red dot scope to mount on an A2 upper.  Fixed sights of the A2 are 2.5 inches above the bore and gives the average user a comfortable cheek weld.  

Putting a scope above the carry handle will give a much large sight/bore relationship and require a chin weld.  Changing from irons to optics will require changing from cheek to chin weld and vice versa.  Putting the scope in line with the fixed sights will maintain the inch sight/bore relationship and allow you to use both the scope and irons without changing cheek weld.  This is called co-witnessing.

There are different ways to co-witness.  A good explaination is on the first post here BUIS/Co-witness thread

thanks  just ordered the ARMS #39 A2 mount.