I actually have the same problem, Apache won't start (Busy). It is probably the result of what I have done.
1. I had XAMPP in C:\xampp on GORT. It ran fine. Eclipse PDT accessed the files in C:\xampp\htdocs\econcurrent.com just fine. I downloaded the database from my remote site and PHPMyAdmin loaded it just fine. My PHP scripts played with it nicely.
2. Having to travel, I copied C:\xampp to L:\GORTC\xampp (L: an external drive) to use with my laptop MARVIN.
3. Having travelled, I downloaded xampp again and installed it by unzipping in L:\xampp and running setup_xampp.bat. It asked a few questions and exited.
4. I then tried to figure out how to move my database from L:\GORTC\xampp to L:\xampp.
5. Figuring I would just ruin L:\xampp, I renamed L:\xampp to L:\xampp2
6. I copied L:\GORTC\xampp to L:\xampp
7. I ran setup_xampp.bat. It just asked 1)Refresh or x)Exit. I refreshed.
8. I tried to start Apache (Busy) and MySQL (OK) from the XAMPP control panel.
9. I ran setup_xampp.bat again. It said "nothing to do".
10. So how do I get old L:\xampp running or get my databade into new L:\xampp2?