Hello Andrew,
The photo is very typical of the appearance of British Army MI on the veldt as the war progressed, so I would say taken in South Africa.
With regards to his time with their 2nd battalion, the relief of Ladysmith comes to the foremost in my mind and there are several things you can do next, if you are in Great Britain, then a visit to the NAM in Chelsea, would be worth doing to find out more about the MI Coys and life of Tommy Atkins in general.
Also, on this site, from the column on the left, select Unit Information, then Imperial Units, then East Surrey Regt, the information has been taken from British Regiments in South Africa by John Stirling, circa 1903.
For a contempory account of the campaign it's self, again, from the menu on the left, select books, then The Natal Campaign by Bennet Burleigh, who was the correspondent of the Daily Telegraph, this is an account of his time in Natal, you will soon get an idea of what went on.
Regarding any post Boer War army service a careful look in WO363 at Kew or on ancestry might be worth doing and you might also take a look at the Great War medal index cards, again, on line.
I am not a navy man, however, if he was in the Royal Navy, the 75 year rule applies, so you should be alright and a visit to the TNA Kew would be worth doing as you should be able to look at most things from 1853-1923.
What you really need is a service number, in 1908 the system gave each RN branch its own alphabetical prefix, so you can see from a quick look which branch that number belongs to, then you can look at any Registers of Seamen's Services or service statements that might have survived and check the medal rolls in ADM171 etc.
If he was an RN officer, check the published Navy List's you will also find service registers up to 1966 and pay registers to 1924.
Can't really think of anthing else right now.
Regards Frank