For the past 5 years, I have provided several DNN sites to a few different charities for free.  Sadly, the DNN site I have is now down.  The problem is that when the DNN site is running the W3wp.exe service and the SQLServr.exe service are taking up 100% of the CPU.  About 70% W3WP and 30% SQLServr.  I haven't changed anything on the site.  I don't know what is wrong.  If I go into IIS and stop the DNN webpage, everything goes back to normal.

When I first got to the server, the C Drive had filled up.  The CPU was pegged.  I've been able to clean off a some of the previous Windows hotfixes and a bunch of logfiles to free up space, but that doesn't seem to be the problem.  The CPU is still pegged.  My thought is that whatever is going on filled up the log files and used up the remaining space on the drive.  I did not touch any files in DNN or SQL Server.  I'm guessing that there is either some type of virus running or something causing the site to go into a loop.

Some of the websites are:

USAHarvest.com (Provides food)
bpwrc.org Business Professional Women of River City
KnobTiger.com (Folk Dance Camp)
HistoricHolmes.org (Historic preservation)

The version of DNN is old: 4.9.1 I think.  I can't pull up the site to check.
It is running on a donated dedicated Windows 2003 server.

Thanks for any help anyone can provide.  

Thank you so much for taking the time to reply.  I was able to shrink the db and I truncated the tables you mentioned, but sadly that didn't seem to help.  Strangely enough the site if left alone long enough the CPU does stop pegging at 100% and eventually seems to go between 70 and 100%, which is enough that the sites are accessible for a while.  So its inconsistent.  Now it is pegged at 100% again.  The processing is still being used up by the same 2 services.  If I stop the DNN sites in IIS, processing drops to below 9%.  I only have 1 non-dnn site and it works just fine.

Would it help if I could provide some logs to look at?  I used to be a developer, so I can find my way around ok, but I'm not that sure at what to pull to look at.  (Its been a while since I've coded).  Give me half-decent instructions and I can pull whatever is needed.

Thanks again for taking time to think through this one.

Troy