The Netflix and Optik software a completely independent things. All the Optik software on the XBOX 360 does is interface the main HD PVR in your house. If you are only wanting to use the 360 for Netflix, then you wouldn't need the Optik software or the $5 per month.
For Netflix you would use the XBOX 360 and it would have to be attached to the tv. One thing, I do believe Netflix requires a GOLD XBOX live account.
For Netflix you would use the XBOX 360 and it would have to be attached to the tv. One thing, I do believe Netflix requires a GOLD XBOX live account.