How do I rip a cd/dvd (data) into an .iso or .cdr?

Look for apps at CNet Downloads or MacUpdate.

Ripping copyrighted or protected CD/DVDs is illegal so we cannot assist you.

If you've calmed down enough, I'll explain a couple of things:

First, a general disclaimer that we're not allowed to help in certain situations is given quite often in order to not only follow the terms of use, but also because we have no idea if the poster is trying to do something illegal or not (I've done it myself).

Second, to address your question: I can suggest the two following apps to rip a (legal) DVD - MPEG Streamclip and/or Handbrake; since I don't know what format your videos are, you can check their websites to see if they can convert yours. Note: MPEG2 Component (available from Apple for $20 as a download) is required for some formats to work with MPEG Streamclip. I've not used Handbrake, but with MPEG Streamclip you will have multiple choices for conversion/export. I do not know if the formats you mentioned are included since I don't run Windows. I do know that it will handily convert to formats readable by iMovie and/or iDVD. You can then burn them from either (if so desired).

What exact format are the data? "Ripping" often involves converting from an inaccessible form (due to copy protection, or different file convention as on audio CDs) to a normal file. If your DVDs are plain data DVDs then you don't need to rip. You just need to copy the files. For that matter you can just use Disk Utility to make image files of the content of your DVD. To get them to iso or cdr here's a post I found on the next step (there may be utilities but I don't have notes on any):

http://www.macworld.com/article/135728/2008/09/createiso.html

and

[Kappy's post: Duplicate a CD or DVD|http://discussions.apple.com/message.jspa?messageID=8965494]

I concentrated too much on your second post and so missed the mention of the "data"; but you got excellent advice from Limnos - I wouldn't hesitate at all following the second link he provided, I've followed that one myself!

Insert the DVD. Open Disk Utility. The, File menu -> New -> Disk Image from (the DVD).

Well, that's weird. Kappy answered this question before, but wouldn't point me to it! I wonder why??

I think because you used the words "rip" (not technically the correct term with data DVDs [http://en.wikipedia.org/wiki/Ripping]) and "DVD" in the same sentence it was easy for somebody to miss the "data" part. 🙂 We have to play by Apple's rules on this forum which includes staying well away from certain sensitive topics. I have seen topics disappear completely (that requires the action of a host) for even asking about a home produced movie DVD. Not always fairly, IMHO, but there are certain topics (and I'm not just talking electronic media) that while perfectly legitimate in one context are considered borderline because of association with illicit activities.

OK, but you did not make that clear. You need to understand these are Apple's discussions, and we must follow their rules. So with questions like yours where the end intent isn't always clear we have to let you know what the limits are with respect to posts on the forums.

A link to how to duplicate a disk such as making a .cdr has been provided below. However, DU is not the easiest tool for making .isos. I have had much better results using Roxio's Toast. Alternatively, you can make a .dmg with DU and convert it to a .iso using any number of freeware tools you will find at CNet Downloads or MacUpdate.

I assume I use "DVD/MASTER" as the option?

Answered in the links I posted earlier.

Yes, selecting CD/DVD Master will result in a .cdr image. Glad to help.

Ripping copyrighted or protected CD/DVDs is illegal so we cannot assist you.

Not so sure. From a Macworld article about dvd ripping:

Editor’s note: The MPAA and most media companies argue that you can’t legally copy or convert commercial DVDs for any reason. *We (and others) think that, if you own a DVD, you should be able to override its copy protection to make a backup copy or to convert its content for viewing on other devices. Currently, the law isn’t entirely clear one way or the other*. So our advice is: If you don’t own it, don’t do it. If you do own it, think before you rip.]