Account exceeded CPU
 

It seems since I installed vbulletin and about 20 hacks I have now found my site crashing with CPU errors. What do I do (in detailed english please) to fix this problem without removing any hacks?

Here is what the page says when the site crashes:

Please contact this site's webmaster.

Wait a few minutes and use your browser's "Back" button or click here to try again.

--------------------------------------------------------------------------------
If you are the webmaster, your account may have gotten this error for one or more of the following reasons:
Your account has used more than its share of the cpu in the past 60 second sliding window.
Your account has too many concurrent processes running simultanously.
Your account has consumed too much memory.
Your site was recently very busy trying to run inefficient scripts.
The solution would be to optimize your applications to use less CPU.
Adding appropriate indeces to your SQL tables can often help reduce CPU.
Using static .html documents instead of painful .php scripts will practically eliminate CPU usage.

Get a new host or upgrade your account to a non-cheap one at that host, the details to fix the issue are explained in your own post.

^ Yep.

Ask your host for the exact reason as well, not just the automated "might be one of these" list.