2- Eset's Nod32 (fastest one available), easy on resources
3- No packet writting, asking for problems. You may want to research Mt Ranier packet writing, totally different concept then Roxio and Nero.
I read some good things about it, problem is few burners support it, I believe some of the Plextors do.
If you get a drive to support it you can download the software here:
I have an older Plextor 24/10/40A that does not support it, next one I get will and I'll give it a try, sure as heck can't be any worse than DirectCD or InCD.