Q: Several odd things - linked or not?

A number of odd things have been happening in the last few days. I'm not sure what to make of them and whether they're all connected, or whether my Mac Pro has simply had unrelated hissy fits and will now go back to its normal uber-reliable self.

Firstly in the dock we've noticed a new icon appear in the dock for a second or two before closing itself and vanishing again. It happens so quickly I can't be certain how often it's going on since if I'm looking elsewhere it registers as little more than brief movement in the dock. It's taken a few days but I've now had a good enough look at it to go browsing through the Applications folder and identify it. It's Epudl.app and appears to be related to an Epson printer I bought and installed last week. I ran it deliberately hoping to have a look at what it's been doing and maybe tweak the preferences but the **** thing closed itself after a couple of seconds just as it's been doing when it launches on its own. Anybody know what this does? I've googled and seen that others have seen it and that some seem to think it's also linked to using Firefox, which personally I don't much since I prefer Safari. I'm not sure if there's anything in that or if it's just because the icons are superficially similar that possibly people think it reacts to Firefox launching. Since it happens whether I use Firefox or not I think that's a red herring. But what I don't know is what it does and whether I really need it. An updater of some kind perhaps? Anybody know?

Second, and possibly third, issues - this morning I flicked the Mac on and went off to boil a kettle. When I came back there was my Vista desktop looking back at me. Uh? I never told it to boot into Windows. So I checked Boot Camp to see if somehow the start up disk had been changed but couldn't get the regular dialogue box. Just stuff about screen and keyboard brightness. Double uh? So anyway, while Vista was up I did an AV update and installed the drivers for the new printer before restarting, and this time I held the option key just to make sure I got the choice. The two disks came up as usual. Selected the OS X one and when I got my normal desktop it tried to autorun the blasted printer CD that I'd stupidly left in the superdrive. After I ejected it the keyboard and mouse stopped responding. Tried a second mouse, ditto. So I had to use the power button to switch off, after which I turned it off at the wall for a minute or two. Turned it back on and did nothing but watch. It seemed to take longer to get to the desktop than normal but it did come up, and the mouse and keyboard work fine.

I've verified the disks and repaired permissions and started looking for info on what's going on and whether or not Epudl.app has anything to do with it, and that's more or less where I am right now. The only other thing is that while I've been typing this it occurred to me to check the Start Up disk prefs pane in System Preferences. "Mac OS X, 10.6.2 on Mac Pro" is the one that's highlighted, but oddly the padlock is open. I'm sure that's not how it was left and it won't lock. It is clickable but all that's happening is that "Click the lock to prevent further changes." is replaced with "something else for a split second and then it's back to how it was before I clicked it. And I really mean a split second - I had to record the screen and play the recording back slowly to find out what it said. "Deauthenticating..." And that's right now after repairing permissions and verifying the disks. Triple uh?

So, anybody got any ideas? Should I trash Epudl.app knowing that I can always get it back from Time Machine if necessary? And is it linked to the other odd behaviour from this morning?