A fix that worked for me…
I run vista with 4g memory. When using nero recode (with or without the burn at once feature) I would always get the out of memory error. Here is a way around it.
You need to change your virtual memory.
For Vista users, go to Control Panel/Performance Information and Tools/Advanced Tools, then Adjust the Appearance and Performance of WIndows, select the Advanced tab, click the change button under Virtual Memory, select Custom Size and make the initial size 512 and max size 512. Then select Ok and Apply.
You have to unselect the burn at once feature and let the file compile first, after that is done, the disc will start burning. I have tried burn at once, and it never works. This is the only way I can get something to burn when using nero recode.
Hope this helps.