eeek.
A quick lookup on the SHeur trojan yields some info.
It disables your firewall and kills your internet.
It also installs a full blown rootkit.
You have some serious issues now.You should consider every password on that machine compromised.As well , any personal info/banking/whatever , has probably been compromised as well..
You need to immediately talk to your dad and find out what kinda personal info was on there , and change it all.
Sorry bud , but it's time to stop trying to clean , and seriously consider reinstalling windows.
