LONG Wait to Load Time

http://tools.pingdom.com/fpt/#!/gjWDlw9rp/dnbrawler.com

My site has an outrageous Wait to First Byte time.. sometimes it loads in 5 seconds.. sometimes 2. But then it spikes to 30 seconds at times and that is unusual and very frustrating. This has been occuring for a bout a week and for a week my traffic dropped exponentially. My first train of thought was to minify JS/CSS and get a CDN and after I did all those things plus optimizing database, deleting revisions, deactivate unnecessary plugin my site scored a B in YSlow that means my loading time is alright. But still my wait to load time is difficult to stand. According to tools.pingdom.com 83% of those 32 seconds were spent waiting on the server. I believe this is either a plugin or widget problem. I have downloaded P3 Plugin Analyzer and it showed me that BBpress accounted for 83% of my site’s loading speed. So I want to reduce the amount of queries spent for bbpress how would I go about doing that. The 2nd most intensive plugin is Buddypress I don’t know where to start about that. I see other plugins that take up loading time which is Widget Logic and Types (Custom Post Types plugin)

Now, I’m on an iPage webhosting service.. but this exceptional wait to load time hasn’t occured before this week–It was only a few seconds before.

I need to pull my site out of this hole before all of my traffic is gone.

I also have a few questions. Does my presence in the back end of wordpress slow down the performance for the users? Because I noticed that the wp-admin/ajax bar is always longer when Im on the dashboard.

And for whatever reason, on many of the loading test sites. I always have two seperate domain entities… my site without the www. and with it.

wwww.dnbrawler.com and dnbrawler.com

Could this be affecting the perforamnce at all?
[site:dnbrawler.com]