for burning data CDs nero 5.5.6. 4 allows for two disc format types to be burned one is mode 1 and mode 2 XA - which one is two be used ?

i click on file > new > cd rom ISO. Now click on ISO. In the format box there are two types as mentioned above. By default Nero checks the mode 2 XA format for data CDs ? Does that mean mode 2 XA is recommended for that ?

for video Cds and svcds it is locked. If i use mode2 XA does it mean i use non error correction mechnism which allows for allowing errors (eg: scratch on CD). Also does it mean less compatibillity with older OSs and CD drives.

i have burned alsmost all CDs using mode2 XA

following info may be useful:
Data format Useable data per Block
CD-DA (Audio CD) : 2352
CD-ROM Mode 1 : 2048
CD-ROM Mode 2 : 2336
CD-ROM Mode 2, XA Form 1/CD-I : 2048
CD-ROM Mode 2, XA Form 2/CD-I : 2324
(taken from http://www.nero.com/en/helptool/137.htm)

According to my understanding there is no diffrence between cdrom mode 1 and cd rom mode2 XA form 1. Is it right?

Also how do i find that the CD is in which format of mode 1 or mode 2? is there any program for that ?

the following link is very important:
http://www.tuketu.com/technology/CD-ROM%20stuff.htm

it gives some more info on the topic

thank you, please do reply back
technogeek
tybms@indiatimes.com