Yes sir. Training users does significantly help as does a comprehensive suite of programs. Limited permissions/accounts can also help in a controlled environment (so users can't go installing Super Smileys 3000 on a whim) and would address the remainder of the user issues above. One reason Firefox has been so successful is it's auto-updating feature for browser and extensions. It doesn't ask, it just does, by default. This is where Adobe has failed miserably. This is why such a large percentage of its Acrobat/Reader and Flash installed user base is outdated and thus still vunerable to yesterday's attacks. The fact that Adobe's aforementioned software has arguably more security flaws out of the gate, auto updates, by default, would significantly assist in helping keep their userbase safe. It's a fairly convoluted process to check your flash version (google for flash version update or similar) and not easily found if browsing their site. (Aside: One app, Grooveshark, actually prompts when you have an outdated version of Flash citing security concerns and provides a nice link to update. Awesome.) I hate manually having to check each of my programs for an update. That's dumb. Almost as dumb as MS patch Tuesday. "We have some serious flaws here, but we can't let you install the fix until next Tuesday. In the meantime, hope you don't get hacked." Sigh. When will people start taking security seriously?

Pst: Your first goal should be to document the answer to your questions. After a few days of dedication to documentation, your ticket volume should drop significantly. Also, you never said what industry/business you were in. If you are fielding that many questions, you seriously need to look at your employee training and reference materials. I am hung up on trying to figure out what your situation is that warrants such helpdesk abuse.

It has been awhile since I have looked at free ticketing systems, but I seem to remember that outside of OS Ticket there was not a whole lot of offerings. Granted, at the very core, a ticketing system is not terribly complex, but finding one with a good workflow out of the box is the difficult part.

Now I know you said free, but I highly recommend you check out Kayako. I personally have not found anything close to the workflow and capabilities this offers. When I used to work for an outsourced support company (mainly web hosting) our system interfaced with customers' Kayako installations almost exclusively. We were pushing 12+ tickets per hour per seat, and the workflow allowed us to do that effectively.

The single feature I miss the most with my current companies ticketing systems is the ability to put tickets on hold (or close, or other custom status) and have them re-open at a specified time interval, say for future requests. Their suite comes with a chat application and a knowledge base, which I don't have extensive experience with, but know they do their respective jobs adequetaly.

In addition to the web interface, Kayako operates extensively by email if you should choose. Now, most ticketing systems I have used do this, but the thing is Kayako's web interface operates like how you would expect email too. Adding people to tickets is simple with the cc or bcc fields (and people get emailed accordingly on ticket status changes). Like I said the workflow is really effective and the interface is superb.

Kayako is only $300/yr for the suite (or $200/yr for just the ticketing system), which is quite reasonable. There is a 30-day demo available. I haven't checked out all the recent features, but last I checked they were working on some more advanced features like desktop sharing, if that be beneficial.