What is the best way to remove a glass block wall?

Put plywood and tarps on floor to protect it.

Start at top. Remove mortar/grout around one block. Tap block out with rubber mallet. If unable to get out you may have to break the first one. Use a 2 inch cold chisel to loosen up blocks and remove.

Keep work area clean.

Chuck

Chuck's answer is very helpful. If you have a reciprocating saw, try using it with a long masonry blade; it might make the job go a bit quicker.