Probably. Check the Drive Compatibility Chart on xlr8yourmac.com. See if anyone has used that drive with an iBook. At the very least, you may have to use a third party driver to get the HD to work. But I suspect that it'll work just fine.
BTW, if you're going through the hassle of opening up the iBook, you may want a larger and/or faster drive. I made the mistake of putting in only a 40GB drive in my ibook. The 60 GB would have only set me back about $30 more. But at least I stepped up to a 5400RPM drive.
I don't see why not. Just make sure it's a 9.5mm 2.5" IDE (ATA) hard drive and you'll be good to go, as that's what all laptops use these days. I put in a Toshiba 60GB drive in a 1st gen iBook (blue clamshell) and it fit fine, no problems.