Mdk,
I have an account with ODL also and I have bought a number of emerging market ETFs, as well as sold options on them using their platform. That said, I have never bought direct equities in those markets, so I haven't had experience with them on that front. Angus Irvine, (Head of Online Trading) is the person who I would direct a query to there at 0044 207 903 6350.
There are a vast number of ETFs available to provide exposure to these markets. A long list is available at ETF Stock Encyclopedia.
The more popular ones (and hence heavily traded) ones would include;
FXI iShares FTSE/Xinhua China 25 Index
EWZ iShares MSCI Brazil Index
DEM WisdomTree Emerging Markets Equity Income Fund
EEM iShares MSCI Emerging Markets Indx
EEB Claymore/BNY Mellon BRIC
This might start your search!