I have/had 31 bitcoins on MtGox; What are my options now? After reading the joint-statement on blockchain, and the fact MtGox is down now, I am scared, what are my options? Is there anyone who can help me in my situation? I purchased those coins for 800$.

Edit:
MtGox files for bankruptcy protection. What is the difference between bankruptcy and bankruptcy protection? I don't know, but I don't think that I am going to see anything from there...
This is generally called counterparty risk - if your resources are in custody of someone else, there is a risk that they go bankrupt and you lose it. And in that case it is too late and your options are limited to making a sadface :( and writing it off as a loss - do note that you can get x% of the loss back from your income tax in most places.

There are options to limit that risk before it materializes - it might be too late for MtGox, but important for the future. All the lessons are pretty the same as historically for 'normal' banks before modern regulation.


Diversify the risk - if your funds are spread out among multiple institutions, then there is less chance in losing it all than putting it all in one basket;
Insure the risk - your bank deposits are insured in most countries, i.e., if the bank can't return them then the insurer pays up to a certain amount. Bitcoin companies currently aren't insured that way, however it means that when some of them get deposit insurance then that would be a serious selling point for their trustworthiness; and if (when?) regulated banks start offering bitcoin services, then you'd get that protection as well. Also, you can purchase insurance for yourself, although it might be unpleasantly expensive.
Reduce the risk - choose the company properly. Reputation certainly didn't help in MtGox case and it's not a guarantee, however, you should be looking at solid evidence that the company is solvent. I.e., you want periodic, publicly visible financial statements that are seen and analyzed by many people and that show that they really can afford to pay all the depositors back even if they have a bad day or a bad year. At the very minimum you need this to be (a) according to common accounting standards; (b) expressed by a company officer in a manner that means jail for him if (s)he lies in these statements; (c) audited by a third party - otherwise these statements are worthless, as if there will be real problems, then they will lie always. Regulators of financial institutions do much of that job for banks; not eliminating those problems but reducing them - for unregulated entities you'll have to check everything yourself.