InCD seems to affect other burning programs, interfering with the burn process.
As a program for handling packet writing (don't ask me to explain 'cos I can't) it seems to be a bit limited in it's inability to be able to delete files on the RW disk. I've used Roxio's DragtoDisk in the past which does allow deletion/updating of files & to me is the better product.
For your second question , I'd used StartSmart & Nero Express & the Data Disc option. Nero will prepare (format/erase) the RW disk when required. Obviously for burning a movie you take the DVD Video files option.