advice with dialer-gen

hI, i AM A newbie here.

I have had so many problems with my pc (with it getting virus after virus)
over the last year. However I have got some reassurance having been recommended
avast.

I scanned my computer today and I found it was infected this time with a win32-dialer-gen(trj)
It said it was in Online services, BTYahoo/Broadband.Ysignup
I have never come across this before, what can it do since I have a wireless network?
Or is it some cover for something more serious like a rootkit?

I have had rootkits, trojans and all including the dreaded virtumonde.
I have now installed comodo firewall and finjan as well as avast and thought I should
be relatively virus free for now!

My only worry is it will come back. How can I can stop it from doing so? I am a bit panicked
over this, please can anyone enlighten me.

Thanks

I suggest one of these antispyware/anti-malware programs:

SuperAntiSpyware Free
Spybot - Search & Destroy
Spyware Terminator (exclude Crawler Toolbar, add on, and ClamAV module)
MalwareByte’s Anti-Malware

Download and post a HiJackThis log.

Let’s not panic
could be a false positive
while you are running an antispyscan
and if you got rid of virtumond you are most likely an old hand at this
what anti spyware have you used?

could you go to virustotal and then upload the offending file and post the results>
thanks