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I read C++ provides additional operators to the usual &,|, and ! which are "and","or" and "not" respectively, plus they come with automatic short circuiting properties where applicable.

I would like to use these operators in my code but the compiler interprets them as identifiers and throws an error.

I am using Visual C++ 2008 Express Edition with SP1. How do I activate these operators to use in my code?

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If you want to have the 'and', 'or', 'xor', etc keyword versions of the operators made available in MSVC++ then you either have to use the '/Za' option to disable extensions or you have to include iso646.h.

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Having made your day, I'd strongly suggest avoiding using the 'alternative tokens' for the operators. I think that most C++ programmers reading the code would prefer to see the usual operators.
Well then, I think it is time for a change. We are supposed to get more descriptive with our variable names and the like right (i bet you'd scream if you saw int i = 3.142;). the token "and" and more descriptive in my opinion than & or &&
Personally, I don't think it helps understanding to use the words instead of the symbols. You'll still have to get a handle on the old style to read code other people write. And adding the choice to C++ doesn't add it to C, Java, C#, Objective-C, or JavaScript. And either way, you're going to have to get "bitwise" and "logical" straight or fall into some really hard-to-debug situations.
I understand that it's a matter of opinion or style, but I think that people are used to the punctuation-style tokens and would find the keyword variants something they have to 'stop and think about'. I'm currently working a project where the existing code mostly uses macros for the logical operators (AND, OR, NEQ, etc), and I must say I don't like it at all... I believe the alternative keyword tokens were provided mostly to aid programmers with non-US keyboards that didn't always have the correct punctuation characters, not an attempt to make them more readable (just more type-able).
A benefit to using the symbol style is that it is easy to distinguish between operators and variables when scanning code. It's a lot harder when everything is alphanumeric text.
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The traditional C++ spelling [*] (just like in C) is && for "logical", short-circuit and, || for "logical", short-circuit or. ! is "logical" not (of course it doesn't short-circuit: what ever would that mean?!-). The bitwise versions are &, |, ~.

According to the C++ standard, the spellings you like (and, or, and so on) should also be implemented, but apparently popular compilers disobey that rule. However you should be able to #include <ciso646> or #include <iso646.h> to hack around that via macros -- see this page, and if your favorite compiler is missing these header files, just create them the obvious way, i.e.,

#define and &&
#define or ||

and so on. (Kudos and gratitude to the commenters for making me research the issue better and find this out!)

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Recent versions of the C++ standard include spellings such as "and" and "or".
@Greg good point, added a footnote on the likely future standard (albeit of, more or less, just "academic" interest at this point in time;-).
'and', 'bitor', 'or', 'xor', 'compl', 'bitand', 'and_eq', 'or_eq', 'xor_eq', 'not' and 'not_eq' are all valid alternative tokens for '&&', '|', '||', '^', '~', '&', '&=', '|=', '^=', '!' and '!=' respectively in the current standard (2003).
VC 2008 is not stricly compliant, see here: stackoverflow.com/questions/198402/…
The and, or, bitand etc. keywords are defined in the original 1998 C++ Standard - see section 2.4.
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