When joining a pool, other than helping to solve the hash and helping to generate revenue for myself, others and the pool owners, am I contributing to the bigger picture of BitCoin?
Absolutely!
Every additional hash power added to the network increases the amount of hash power an attacker has to supply if they want to rewrite the blockchain history. The more honest hash power the better the odds that an honest miner will solve the next block. Increasing the hashing requirements for attacking increases the costs of attacking. If 1 million people can each increase the costs of attacking by $1, then the attacker has to spend another $1 million to gain a majority of the network hashing power.
Outside of development (which I lack any skill for programming) and evangilism, what other ways can I or my machine contribute to the bitcoin community?
Offer products or services for sale and accept bitcoin as payment. Use bitcoin merchants and services (such as bitcoinstore.com) preferentially even if it costs slightly more than a non-bitcoin counterpart.
