My first ever investment

After years of not having invested in anything, I finally have decided that it is probably less risky to make an investment than not! As detailed in several posts I believe that there is a risk of the pound going through a period of very high inflation and so taking a serious nosedive on international markets.

So here's my investment of choice: ETFS All Commodities, as I understand it (and please tell me if you think I've got it wrong!) this is an investment which tracks the price of a basket of commodities like gold,copper,oil,assorted agricultural produce etc. Now its important to note that its tracking the price of the stuff itself, not the success of companies that make it.

There are many reasons I've chosen this:

1. Its diverse.
2. Commodities can never go out of fashion, nobody is ever going to say "Oh that copper junk, who needs that!" and this will be true for decades to come.
3. Unlike companies, commodities can never "go bust".
4. Many commodities, like oil, are running out and/or getting more expensive to extract (see this if you need persuading).
5. The worlds population is expanding, creating ever more demand.
6. It seems to me that the cost of commodities, in the very long term, should increase at least in line with world average (erm, maybe total) earnings.
7. After a big crash (like now) is probably a reasonable time to buy in.
8. I wouldn't matter if the UK (where I'm from) had some economic catastrophe as long as most of the rest of the world was doing ok and could hold up commodities prices.
   
9. Relatively cheap to invest - through Interactive Investor its £10 to buy in and £10 to sell regardless of the quantity. Then 0.49% P.A. management. No "stamp duty".
10. Buy or sell at any instant.

The only thing that worries me about this investment is that I haven't fully understood the mechanics of exactly how it is arranged "under the hood" and I don't fully understand the insurance that backs it up.

I would very much like your opinions on my investment.