Issue with .exe and Command Prompt

Ok, I've done something completely terrible, changed all of my .exe files into something else (By accident, I'm gifted). I was trying to open a .exe file to modify it to allocate more memory to it, Minecraft, and didn't have the right program, it was Java SDK apparently, but could only find Java JDK upon searching, and now no programs will open, or rather, they will open, but through the path that I accidentally changed it to. Which happens to be the command prompt currently, and before it was notepad, and before it was JDK Development tools (I didn't know what was happening, so kept changing it) (And command prompt was broken before I changed programs to open through it. I must stress though, this isn't a virus, this is my own stupid mistake.

To get internet to open (to post this), I had to find a file my computer didn't recognize, and try to open it, prompting me to see if I wanted to search the internet for it, and voila, I got this open.

If there is anyone, who may have an knowledge of how to fix this problem, without using command prompt, a .exe program (regedit is un-openable as well), if you could enlighten me I would be most grateful.

If you need screenshots of anything I will be happy to take some and get them here.

Edit: I've also tried copying the regedit program from another computer to this one via flash drive but it lost it's .exe upon opening on my computer.

Thanks - Hastings

Hello Hastings, and welcome to Seven Forums.

Don't worry. You just messed up the associations for exe files. You could download and merge the .reg file for the listed EXE option in the tutorial below to fix this. It will restore the default associations for .exe files.

Default File Type Associations - Restore

Hope this helps, :)
Shawn

You're most welcome. I'm glad to hear it's fixed now. :)