Your problem could be a bunch of different things, a corrupted source file for one, instead of buring to a disk try buring to a ISO file or to a folder vice a disk and see if you still get a problem of somekind, it will help to pin down the cause, it could be not enough memory or disk cache space, firm ware problems in the burner, burner problems, burn media not so hot, alot of times this happens as some branded media switches suppliers,
To see what variations for “Internal target failure” there are, do a net search for the same.