I'm using my HP 5160 to print directly to DVDs using both Acoustica and Surething but the labels aren't being printed correctly. (eg. there is always a white border and the label is printed off-center)

I'm trying to calibrate it manually (eg. print a label, adjust the settings to what I think they need to be and then re-print), but I'm wasting a LOT of DVDs and the calibration still isn't anywhere near correct.

What can I do to calibrate these programs to print correctly?

You have to do it manually in page setup. What you can do is just add a higher amount of bleed to your print. Also you should measure the printable portion of your discs and input that into page setup. Then do a test print and tweak it from there.

In Acoustica, go here and make your adjustments.
You can also print a "ruler" with Acoustica to physically measure your printable area.
The radio button for that is in the dialog box that appears next.

For SureThing v5 see this tutorial. It's written by "Pete" who is an Admin at the SureThing Forum. Like Explicitez said it's a process of measuring your disc and making the bleed adjustment and then testing it. Btw, there is no calibration for discs, just labels with SureThing.

I forgot to ask - does the OP (or anyone else) have a preference between Acoustica & SureThing? I have 2 days left on my ST trial and just found Acoustica, which is about $10 cheaper.