http://www.cds.com/capacity.htm
On this web page it says I can do upto 805,920,000 (768mb) on a cd and I have Nero 6.3 but I selected the iso format and the xa mode two and now its saying that the cd can’t hold that and I need a cd with a larger capacity. Help please. What am I doing worng.
What CD’s are you using? There are 99 minute CD’s but not all burners can use them.
Just because the page you referenced says that you can burn up to that amount doesn’t mean that your burner and discs support it.
General Relativity is only a theory.
I do have a CD rw capable of overburning I have an MSI that goes 52x and a CD that with a 890 mb capacity. but I still can’t overburn with both of those.
Also with a regualr CD how much can you hold (max) in it
data -> 700 mb on an 80 minute cd
audio -> 800 mb on an 80 minute cd
xa mode -> forget what that one is and how much it can hold. not very common. you can enable overburning in your properties dialog within nero.
but how do you enable nero to do overbuning
File -> Preferences -> Expert Features.
Maximun setting for CD overburning is 150m 59s 74f. 
Regards,
ET
but I thougt there was more to it than that like setting the rec. time like Min sec and Mil sec.
what do you mean? 
ET