Firstoff, try and get your hands on a clean computer (WITH antivirus software) and a flash drive.
Secondly, since it's downloaded, install by renaming the "mbam" setup file to something random, anything will do. If it installs, but does not run, go into the Malwarebytes directory (C:\Program Files\Malwarebytes Anti-Malware [I think]). Go to Tools>Folder Options (in the menu) and "Show file extensions for known filetypes." Then, rename (mbam.exe [again, guessing]) to something like "blah.com" This should theoretically fool the malware and allow you to run the software and remove a bunch of the junk that is plaguing you.
Now, by the looks of it you should try using other anti-malware programs as well. Downloading Avast 5 free will allow you to schedule a "boot-time" scan which I highly recommend you utilize so as to insure malware can be caught before it loads. Spybot Search&Destroy, Ad-Aware, Microsoft Security Essentials, AVG Free, and Avira Anti-Vir Personal are all feasible and recommended choices to run.
And, as with the malwarebytes executable, if any of the above setup programs refuse to run, rename the executable! This can fool the malware!
If you need any more help, just ask.