I just recently downloaded the client and have been having trouble getting it to run. I updated my java to the most recent version and I have the jar file in the correct location.
I have tried changing the autodetection of java to the location of my java, but that didnt work either.
Here is what I get when I try to run it

Autodetecting java
Testing default folder
Checking C:\Program Files\Java\jre6 folder
Found java in C:\Program Files\Java\jre6 folder
Checking C:\Program Files\Java\jre1.6.0_02 folder
Found java in C:\Program Files\Java\jre1.6.0_02 folder
Checking C:\Program Files\Java\jre1.6.0_03 folder
Found java in C:\Program Files\Java\jre1.6.0_03 folder
Checking C:\Program Files\Java\jre1.6.0_05 folder
Found java in C:\Program Files\Java\jre1.6.0_05 folder
Checking C:\Program Files\Java\jre1.6.0_07 folder
Found java in C:\Program Files\Java\jre1.6.0_07 folder
Starting java from "C:\Program Files\Java\jre1.6.0_07\bin\java.exe"
Exception in thread "main" java.lang.NoClassDefFoundError: com/mojang/minecraft/
MinecraftApplet
        at java.lang.ClassLoader.defineClass1(Native Method)
        at java.lang.ClassLoader.defineClass(Unknown Source)
        at java.security.SecureClassLoader.defineClass(Unknown Source)
        at java.net.URLClassLoader.defineClass(Unknown Source)
        at java.net.URLClassLoader.access$000(Unknown Source)
        at java.net.URLClassLoader$1.run(Unknown Source)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(Unknown Source)
        at java.lang.ClassLoader.loadClass(Unknown Source)
        at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
        at java.lang.ClassLoader.loadClass(Unknown Source)
        at java.lang.ClassLoader.loadClassInternal(Unknown Source)
Caused by: java.lang.ClassNotFoundException: com.mojang.minecraft.MinecraftApple
t
        at java.net.URLClassLoader$1.run(Unknown Source)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(Unknown Source)
        at java.lang.ClassLoader.loadClass(Unknown Source)
        at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
        at java.lang.ClassLoader.loadClass(Unknown Source)
        at java.lang.ClassLoader.loadClassInternal(Unknown Source)
        ... 12 more
========================================
Warning: lib\minecraft.jar not found.
Did you read instructions / download it?
========================================
ERROR: Failed to run minecraft
JAVA6="C:\Program Files\Java\jre1.6.0_07\bin\java.exe"
Press any key to continue . . .

I am open to any suggestions currently. Please help.