Go buy yourself a low-velocity power nailer from the hardware store. Remington is the only brand that I've seen, you put a .22 shell full of powder and a special nail in it, put it up against the 2x4 and hit it with your hammer(wear ear protection). You will also need this for nailing your baseplate to the concrete but be sure to use the special galvanized coated nails to go through the green treat lumber that you should have at the bottom of your wall.
It's not too expensive the gun should cost you around $20, the shells $5 for a box of 100 and the nails $10 for 100.
Good luck and post pictures and updates so we can see what your doing.