Ya you should only stick with one anti virus software just like akaru said. For example, you can have kaspersky and spybot search and destroy but not kaspersky and norton.
Anyway i use kaspersky and you should try Malawarebytes' Anti-Malaware, Malawarebytes saved my computer. (it's free, so get it).
I really can't help you too much unless you post more info about the trojan. Try searching "how to fix this trojan." Maybe you'll get something useful.