Anita,
Thanks for the update. And, that's good you are doing a backup.
Now, I don't use Time Machine for my backups, preferring to use SuperDuper!. With that program, it makes a bootable backup on my external drive (actually I do it twice, for each of my machines, to two different external drives). If I did not have TechTool Pro on my machine, I could boot my machine from that backup, and run Disk Utility from there. Disk Utility can also Verify and Repair a disk/partition. In my case, I would instead use the more robust program Disk Warrior on that bootable backup to do any repairs. (I have, a couple of times, done that).
Given that I do not use Time Machine, I am not sure how easy it is (or possible?) to boot a Mac from a Time Machine backup. If you can boot from that, you could run Disk Utility from there, and this Verify and Repair the Mac partition on your internal drive.
Now, it's important to understand that Oynx and Disk Utility are two different programs, and except for Repairing Permisisons, they do different things. Onyx cannot repair a disk. It can clean off quite a bit of unnecessary stuff from your machine. That is what it is really good for. Disk Utility, on the other hand (as mentioned above), can repair a disk/partition.
So, here is what you should do:
1. If you can boot your Mac from the Time Machine backup, do so, and run Disk Utility from there. Perform the two functions it does: Verify and Repair Permissions (you might need to repair the permissions a couple of times to get it "clean"), and then Verify and Repair the Mac partition.
2. If you can't boot from the Time Machine backup, download SuperDuper!, use it to make a (bootable) backup on your external HD, then start up your Mac from that backup. You can then run Disk Utility. (I would still download SuperDuper! and make a back up with it).
3. After Disk Utility runs, re-boot your machine from your primary boot partition, and see what happens.
4. No matter how #3 goes (not sure if it will "help" your issues with Word, and/or your battery issues), you should still download the OS 10.6.8 Combo Updater, and install it. It will not hurt, and it could help. Then again, it might already be installed, but again it will not hurt to install it again, just to be sure.
5. Re-start your Mac, and see if that helps with anything.
6. Backup your Mac, with whichever program you prefer (myself, I would use SuperDuper!)
7. No matter what happens via #5, download, install, and run the correct version of Onyx from the link I provided above. I would even run its' Repair Permissions "piece", just as another measure. Who knows what it will find?
8. At this point, and without seeing the results, it's difficult to tell whether or not you can then apply the Office 2008 updates (there will be 3 of them). But, I suspect it's been a while since any maintenance was done on your machine. So, that is why the next step should be to run a more robust Disk Repair program like Disk Warrior or TechTool Pro (by the way, a new version of it just came out earlier today).
As I mentioned above, if you choose to purchase TechTool Pro (cost $99 (US Dollars) in the US), it will install s small, bootable, and isolated partition called eDrive on your internal drive. You could then run TechTool Pro from that eDrive, and use its' many useful functions.
In any event, let's see what happens after you do 1 (or 2) through 8 before proceeding any further.