This happens to me with every modpack, it tries to boot, then a warning pops up saying: Java has stopped working, and looks for a solution. Vanilla minecraft works, but not modpacks (FTB or TEchnic).
I tried deleting every.technic, and using the.JAR instead of the.exe, nothing is working.
Java stops working while booting hexxit/Tekkit?
Kevin
Try reinstalling your normal minecraft. If that doesn't work reinstall any program or delete any files that have to do with tekkit such as Java
Kevin