My Minecraft Launcher Keeps Crashing?

So two days ago I downloaded heaps of mods and put them into my mods folder in my.minecraft file. After that my minecraft wasn't working so I took all of the mods out of the folder and it worked fine once again! So today I decided i would try again so I downloaded 3 other new mods and put them in the folder but it kept crashing! So i once again took the mods out but my minecraft was still crashing! I looked up online how to fix it and a guy said to delete the.minecraft file then run minecraft again and that will fix it… So I did but now my.minecraft folder only has this "launcher.pack, launcher.pack.lzma, launcher.pack.lzma.new" in it, i don't know what to do! I read another forum and he said to delete everything to do with minecraft on you computer and that will fix it. So i did but when i reinstalled it the same thing happened (launcher keeps crashing)! I'm really worried I can't do anything to fix it so please help me!

just let me know if you need any more info!

You have to press play in the launcher to get the other.folders, downloading it again alone isn't enough. As for the mods, are you sure the mods you are downloading are the same version of minecraft your putting them in? (1.6.4 Mods have to be played on 1.6.4, same with all other versions).