Malware prevents access to downloads

Hi,
I'm a newbie here with serious malware problems. Fundamentally my browser has been hijacked and I can't access any useful sites for help (this post is from a different computer). I have Mcafee, Spybot Search and Destroy and recently Spyzooka. Mcafee does nothing useful, the other two won't complete execution and I can't access their websites nor can I access any Microsoft websites. I have read all of your interesting info but alas, I can't even start because I can't get even download CCleaner on the problem computer. In all of these examples, I am redirected to a wide variety of of troublesome sites. So how can I follow your recommended procedures if I can't reach the various download sites? I'm hopeing for a breakthrough but I'm willing to launch a nuke on this thing.
Oregonjack