need help getting rid of trojans, viruses and malware

when i start my computer the following happens:
1. random music begins to play when im away from the computer
2. Pop ups keep occurring, esp. ones with norton antivirus
3. my computer freezes all the time
4. all these notifications of spyware and such pop up constantly

how do i get rid of them all and clean my computer?

Welcome to Lockergnome.

Read this topic and post the HijackThis log here when ready.

Also do the below:

Go to http://www.bleepingcomputer.com/combofix/how-to-use-combofix and follow the instructions on how to install the Recovery Console and run ComboFix. Go through all the steps until posting the log part. Post the combofix log here.