See Building Science on basements.

Half inch would be insufficient by itself in most climates. While a vapour barrier (plastic) may be required by antiquidated building codes in some areas, it's not necessary. However, Dr. Lstiburek of Building Science says it won't adversely affect the insulation.

If you're applying foam board, be sure to run horizontal layers of adhesive on the wall to eliminate air flow between the board and the wall.

Here's DuPont's instructions that are applicable to most other foam boards.

Note: Rather than using Tapcons, consider non-conductive fasteners.

I hope you have a 6mil vapor barrier down under your concrete floor. Some areas require 10mil. For walls the exterior drainage and coating should be done to address moisture.

Is this a new build and what climate? You can't go wrong with 2" of XPS foam attached to the walls. Then you can cover up with stud walls (if you need to run electrical and/or plumbing), or apply gypsum board (or 3/4" plywood) directly over foam. The foam board acts as a vapor barrier. If using studs, you can add unfaced batts to increase insulating value. If in a cold climate and not adding batts, you may need to increase foam to 3" if you have to meet code.

Thanks guys for all your replies.

To give you more context this is a 1964 house, so not a new build.

As for climate, I live in southern Indiana.

I do have a sum-pump installed with french drain installed all around the parameter of the house inside.

Basement is about 1000sqrf and it is all cinder-block and the outside of the house is all brick if that makes a difference. The block seems to sweat and if there is hard rain it seems to get moist in some spots but the block seems to keep mostly dry even during the harshest of weather.

I did paint the cinder-block with Drylok.

I the thing i want to understand is if it is even worthwhile to install foam boards. My basement seems to stay cool in the summer and warm in the winter. So I'm wondering if I install the foam board will that help with heating and cooling? The way I understand insulation is that it should keep "inside temperature inside and outside temperature outside".

So even though my basement keeps cool/warm right now, by installing insulation will it reduce the work load of my furnace and/or A/C resulting in lower heating and cooling cost

Worthy, you say to apply the adhesive horizontally, is that with vapor barrier being in place? because without vapor barrier shouldn't I apply the adhesive vertically so any moisture can run down?

Dan1888, Why do you say that you hope i have vapor barrier installed under the floor?

A concrete floor is porous. If you have a vapor barrier under the pour, you limit how much moisture migrates into the space. Some jurisdictions require a 6mil and some now say 10mil as part of your build. I put 6mil under my slab and garage space. No way I would leave that out. Even for under a garage. It makes a major difference.

Ohh Yehh, with a new slab to be poured i defiantly agree but can't do anything about that now. lol

I too hope there is some kind of vapor barrier down there.

" To give you more context this is a 1964 house, so not a new build "

" I too hope there is some kind of vapor barrier down there. "

Left from the 1960's, I doubt it......................Roll with the advice worthy gave you up top from Dr. Lstiburek

Worthy, you say to apply the adhesive horizontally, is that with vapor barrier being in place? because without vapor barrier shouldn't I apply the adhesive vertically so any moisture can run down?

Assuming your basement is not leaking, the water running down the walls is a result of condensation. Sufficient extruded polystyrene or expanded polystyrene will stop condensation. Horizontal glue lines will break up air currents between the wall and the insulation called convective looping.