Reboot, type dmesg and check that it says something like:
EXT3 FS on hda1, internal journal
EXT3-fs: mounted filesystem with ordered data mode.
If it does, then you're set.
Incidentally, it's much easier to use ext3 because you CAN always mount it with any ext2 (not just ext3) utility (i.e. an old boot disk, that windows driver etc). But yes, it is MUCH HARDER to recover deleted files from journalled filesystems but not necessarily impossible - it depends on the design. Some journalled systems do stuff like zeroing deleted files etc. Recovering a deleted file is not something that you can just throw a utility like an e2undelete at, though.
Incidentally, ext3 has three modes of journalling. One that's fast but not-so-safe, one that's completely safe but incredibly slow and one that's middling. The default is the middling (obviously).
http://en.wikipedia.org/wiki/Ext3
I believe, though, that the worst that can happen with the default is that if you lose power while in the middle of writing a particular file, you will lose whatever parts of that file haven't made it to disk (as non-journalled systems do) but you shouldn't EVER lose the structure (i.e. you should never need to fsck, the linux equivalent of scandisk, such filesystems, should never get cross-linked chains and all that other rubbish and no other file should be affected).
This means that, short of hardware failure, the filesystem shouldn't ever "break" or lose files/directories except for those that you were in the middle of writing (which may not be complete but should still exist).
But then, if you were to crash halfway through writing a file on anything but a fully journalled, incredibly slow system, the chances that the resulting file will be useless (definitely if it's binary, almost certainly if it's text).
So ext3 = readable as plain old ext2, but journalled enough for most purposes, secure enough that your filesystem won't corrupt if you do have a power outage, fast enough to still manageably use it, at the cost of a small bit of disk space.
Reiser is better at storing lots of small files, generally quicker overall, takes less disk space, but you lose the easiness and convenience of ext3 (i.e. you can't convert an ext2 filesystem to a Reiser as easily as to ext3).
