I think the short answer is, "No. An aborted process can't be resumed with anything resembling ease."
If the other users were "smart enough" to be capable of pausing the task, so you could resume it later (if they were so inconsiderate as to not resume it when they were done), that would be a different story. Many encoding systems offer a pause/resume option, and I think Handbrake does too.
I get the feeling that this isn't a software problem so much as that you're sharing the machine with woefully ignorant other users. Maybe moving the encode function to a machine that other users are less likely to screw up is an option worth considering.
[edit]
I don't mean this to be a flippant answer. I've had issues like this, and had to explain to more than one person how big a nuisance they were being, and that if they didn't quit acting like a thorn, I'd have to cut them off from using the machine I controlled. And other users I had to cut off entirely because they couldn't restrain their need to be jerks.
6Sorry for the stupid idea but: how about locking the screen? – miniBill – 2012-07-08T21:40:20.897
NO I cannot lock it the screen. The others users is my elder brother lolzzzz. They would shout at me, if I do this. – FrozenKing – 2012-07-11T05:13:46.793
Would creating different users work? – miniBill – 2012-07-11T15:57:02.430
I would suggest you edit your question to ask for the actual problem instead, like, how you can prevent others from stopping the conversion process, rather than asking for your attempted solution. See: What is the XY problem?
– slhck – 2012-07-15T18:01:12.700Otherwise, if you don't want that, then of course there's nothing we can do, but then I'd be really clear about the fact that you don't want answers that provide workarounds. – slhck – 2012-07-15T18:05:56.927
Waste of 50 bounty points !!! – FrozenKing – 2012-07-23T13:42:59.287
Sometimes when you ask a question, you won't like the answer. And other times, the question you ask won't have any good answer, so (like happened here) people will try to come up with options that work-around the impossible-to-fix source problem. If there were any direct answer to the question you asked, that would have been the first thing anyone would respond with. Obviously, your situation is far more complicated than "resuming video conversions". If you rephrase the question or make it more clear what you really need, you'll probably get better results. – killermist – 2012-07-24T12:53:44.367
@killermist My question is just simple !! If ppl would even tried to answer this question without been a bounty question, I wouldn't put my 50 bounty. "Everything has a value dude". If I am putting bounty to my question I expect to get a good helpful answer. I appreciate the answers the other user gave but it was not the exact thing I wanted. – FrozenKing – 2012-07-25T10:21:33.340
"it was not the exact thing I wanted.", in this case is a problem, because it doesn't exist. You're dealing with a hard situation where you don't have administrative control of the machine. Without that, you're just plain out of luck. To expect us to be able to help you to work around that kind of situation is unreasonable. – killermist – 2012-07-26T00:50:16.173