Start over dude.. Delete your .minecraft and try again....Start by creating a new profile in launcher and choosing the 1.7.2 version in the launcher and run the game so it downloads the required jars it needs. You NEED to do this for EVERY version of minecraft you choose to use. Just run it once to get to the game screen then you can quit. Now go to forge site and download the 1.7.2 latest recommended 'installer' version of forge. Go here for forge: http://files.minecraftforge.net/
Now run the installer on clientside. And it will tell you if it was successful or not. Before you run the game or want to use different versions at another time you need to make a new folder in your .minecraft. Just navigate to your .minecraft folder and inside create a 'new folder'. You can name it whatever you want, but for simplicity I will call it 'forge172'. Once you create this folder in your .minecraft, open up the launcher again and 'edit profile'. Check the 'game directory box (right under the profile name) and add this folder to the end of the directory. (like so: c:\user\name\appdata\roaming\.minecraft\forge172)<---should look something like that. Now go down to 'use version' and find the 1.7.2 forge version you just installed and use it. Now you must run the game one more time and let forge set-up. Again, once you get to the game screen and see forge is there you can again quit. Go back to your .minecraft folder and open the 'forge172' folder we created, and in here you should now see the 'mods' folder, 'config' folder, etc. That newly generated mods folder is where all your mods should go, make sure you read the mods OP and make sure they don't have a 'core' or something you have to download too in order for it to function. If forge is working and you still crash...it is due to a mod.Might try asking there if failed.
Remember, you need to run the vanilla game at least once for EVERY version you wish to use. Create a new folder (with unique names) and point the directory to it for every version as well. And you must always run the game(again) at least once with ONLY forge too. These new folders you create is how you can have multiple instances of minecraft on whatever versions. All mods.configs,save, etc. will generate inside these new folders instead of your .minecraft.