Clearly I'm not very familiar with Islam, but I prefer to become knowledgeable in a wide range of things, so if I'm asking a question here, or speaking to a Muslim, should I strictly use "Allah" to refer to the creator of the universe or does saying "God" mean the same thing?
Yes and no.
"Allah" is the Arabic word for God. However, in Arabic there is a distinction between "Allah" (God, i.e. "The" God), and "Ilah" (god, i.e "a" god), a distinction which is easily lost in English where the same word (capitalization notwithstanding) is used for both.
Both terms are used, for example, in the shahadah when Muslims say "Laa ilaha illallah": There is no god (ilah) except for God (Allah).
Because of this ambiguity, many Muslims do prefer to avoid the use of the English term "God"; but again, many have no problem with it at all. It's really more a matter of culture and personal preference than anything else.
In my own experience, those who are likely to take issue with the term would be more conservative, especially those raised in a non-English environment. However, native English speakers — especially those holding to the more liberal flavours of Islam — tend to be fine with either.
Peace be upon you, Molana Tariq Jameel once said in his speech that do not call 'Allah' as 'God'. He also said that 'God' is a farsi word meaning 'immortal' whereas 'Allah' does not mean like that and he has chosen only 'Allah' for Him. He further said that saying 'Allah' makes one's memory sharp. Therefore use 'Allah' anywhere as He has chosen only 'Allah' for him.
Muslims usually avoids the word God as it has the opposite gender, Goddess. But the word Allah has no opposite gender.
The most important fundamental concept of Islam is that the Almighty is one and only. He has no child, no father, no mother and no any other relationship. As God has opposite gender, telling Allah is one kind of admitting his wife. So, it is Shirk, which is enough to get out of Islam.
Does the word actually matter? The definition of the word God does not say that "For every god, there is a goddess". Man is independent to call his lord by any good word he likes. One can define his god in his way. So, how is it related to Shirk?
Extremism is a bad thing. So, before relating anything with shirk, we have to think twice. However, it is better to avoid the word God, but it is not prohibited as I could define my god in my way. We could encourage people to use the word Allah instead of the word God, but we could not compel anyone not to use the word God.
And Allah knows the best.