Problems Burning .ISO Image With Burning Rom - Please Help

im having problems burning an .iso image with nero burning rom. the image is of gta: san andreas & there's another one of battlefield 1942. ive tried burning them with imgburn, magiciso & alcohol 120% but it says invalid or unsupported image file format. when i tried to burn it with nero, it says foreign image file: the entered block size does not correspond to the image length. the block size my be wrong. do you want to correct the value or ignore the problem? when i go to correct, where it says block size it says 2048. i tried changing the value to 2352 as its the only other value, but it still wont work. i tried mounting the image with alcohol 120&, poweriso, but it says mount image failed. the image file is invalid or unsupported. does anyone know whats going wrong? i want to be able to burn these to disk or even mount them to a virtual drive, but it wont let me. if i right click the gta iso & select properties the size is 658mb(690,878,720 bytes), but below that it says size on disk: 690,880,512. i would appreciate if someone could give me some help or suggestions as i dont know whats going wrong. thanks