windows 7 cannot repair start up

Ok I am running windows 7 and after my virus program found a trojan it crashed and will not make it past the "windows is starting up" screen. It goes to "windows is loading files" files then the start up repair screen comes up with the options of:
system restore
recovery
small image recovery

Check disk

and repair start up which doesn't work.
I have used a avg boot cd to get the virus removed, deleted or renamed but it still cannot start windows. I tried system restore and it couldn't the first time and now it gets stuck. I put in a repair disk and it attempts to repair but doesn't. Any suggestions? Please