I don't want to beat a dead horse, and if people don't want a feature like this then they don't want it, but...
starkey: yes, it is easy to switch to .doc format in OOo IF you know that you even have to do that, AND you know how to do it! People not very good with computers might not be able to figure it out by themselves before they are inconvenienced by it. "Tools-->Options-->Load/Save-->General and then find the box on the lower right, and then scroll down and switch it from OpenDocument Text to Microsoft Word 97/2000/XP" might be trivial for you or me, but it's not for many people that I work with. My friends, family and co-workers need someone to either do this for them or tell them that they need it done and then show them how to do it. A guy I just did this for said to me, "Oh, computers are so complicated!" These are not stupid, incompetent people--they have just never operated out of an MS environment before, and it might not have ever occurred to them that such a thing might be necessary, and if they do know they need to do it, it might take them a while to figure out how. Don't look down on them--this is the vast majority of computer users.
newW2: I just tried to open a linux-made .odt document on windows using Word, and I couldn't get it to open. Double clicking it brought up the window that says it doesn't know the format, and that it could look on the web or give a list of applications. Choosing Word on the list still doesn't open the program correctly. I used OOo 2.0 rather than 2.2, so maybe that's what caused the problem, but my experience was not as easy as yours. I haven't found any messages on the web that says that .odt documents will open as .rtf in Word, but I have found some messages saying that you can't open .odt docs in Word. I also see that Sun made a plug-in for Word to allow it to open .odt documents. So it seems to me that many people have not had such an easy experience with this as you.
I am not a pusher of M$ crap--I want EVERYONE to stop using M$ software---TODAY! I live in China, and it's INSANE that almost EVERYONE here uses M$ stuff. They need to STOP IT! NOW! But, that's not going to happen immediately. Most people in the near future are probably going to take some time before switching to linux or other alternatives, and people who switch earlier are going to need to work with M$ until everyone switches. Again, that's no big deal for me or probably anyone else reading this board, but it is a problem for people who are not computer savvy. Mint does all sorts of things for people who are not computer savvy. Like: installing flash, installing mp3 support, installing codecs, automounting ntfs partitions with read-write support, etc. All of these things are dependent on or linked to things proprietary, closed-source, not necessary, and they are things that people could install by themselves if they want. But in this as yet imperfect world, some people want these things right away with no fuss, and mint provides them with no fuss to the user. It's precisely for this reason that I think that Mint is at present the version of linux best suited for easy adoption here (barring the problem of Chinese support not being included on the CD--that's why I'm interested in making a version with Chinese support).
The OpenOffice first run option I am proposing is not meant to be a permanent solution to lock OOo users into an M$ format. It is meant to be a temporary solution to help non-computer-savvy people in M$-dominant environments to switch to linux with a minumum of trouble.
Again, if people don't want it, then they don't want it. This idea is just coming out of my experience of having to do this for people who I convert. If people don't want an OOo dialog box that's fine. Maybe a mention in the tomboy note that starts on after installation.