Is there an add-on that makes this fairly easy to accomplish? We'd only like to export/import blog entries and the field groups are identical on both EE installs.
I don't think there's any addon out there for such a purpose and I'm not sure I'd trust it entirely if there was in comparison to grabbing the data from the database directly.
I can't remember the EE1 DB schema but they should be fairly easy to get to. In EE2 all your channel data is listed in
exp_channel_* and comments in
exp_comments. Possibly also
exp_comment_subscriptions if there are any. It should follow a similar suit in EE1 so you can export the data from those tables and import into your new database. Just double check if you have any addons in use which may link into channel entries and be sure to install those wherever it's being moved to and grab their data too.