Mac OS error?????

i am trying to record to a dvd and i am using a DVD -R and everytime i hit record (i've tried several different programs and even just using finder) i get an error message that says:

"could not record the disc because of a mac os error" result code =-13780

please help! thank you!

Go to System Profiler found under About this Mac, select disc burning and make sure the installed/external burner is capable of burning DVD-R. Some burner cannot handle DVD-R or even CD-R and use DVD+R.

thanks for the tip, i am ok there. i found two sources of my problems apparently toast 7 and popcorn 2.01 don't work with leopard...unfortunately.