Computer Halts When Browsing

Recently my computer has started to freeze up or 'hang' (I think that's the right term). I use my computer for internet access almost exclusively, be it browsing, internet telephony, downloading stock data, or cleaning the fish at the poker tables (but more on the poker app in a second). I am using FireFox with tabbed browsing; everything will be normal then suddenly I won't be able to tab back and forth between open windows. Clicking on any icon on my computer brings about no response. The solution is always the same I click control alt delete and bring up the windows security dialog box. I click on Task Manager and nothing happens. THEN - I click on Task Manager a second time and the TM pops up. The weird thing is I don't have to do anything else. Task Manager shows all programs as running and then I simply close Task Manager and all programs are again functioning normally. Somehow the process of opening the TM clears the freeze-up. This is happening with all programs EXCEPT- my poker client, which doesn't freeze up at all - I can play poker or chess through the ICC BlitzIn client and there is no freeze-up. It is only when I am browsing, or using the Skype internet telephony client, that this happens, and I believe it is only when the browser is up. I have run complete Trend Micro Scans which discovered a few problems including asujuja.exe. I fixed all problems found at Trend Micro Housecall. I ran a bunch of other scans and cleaners that I have. I am going to do a defrag of my HD tonight. I downloaded the latest version of FireFox and installed it over top of the older version I had but this didn't work. Does this ring any bells with anyone? Why does the Task Manager clear this blockage and why must I always click on Task Manager TWICE to get it to work (this is the weirdest thing about the problem).