Bass47: Nice list, thanks. I'm planning to get into this games for a long time. Always liked the Fallout games especially the first one.
You'll pass. I coached a guy for IELTS, utterly unprepared, couldn't write a coherent essay to save his life, and he passed.
Reading / grammar: read more. Read, read, read, read, read. You have to get a feel for the language so you know the answer to those "insert preposition" questions before you even see the options (which honestly only serve to confuse). This is where games and other entertainment is actually useful.
Writing: buy an IELTS self-study guidebook and study that. There are usually examples of shitty writing submissions (what not to do) and good writing submissions (with room for improvement). You don't just have to write, you have to write a specific thing in a specific style, cover all the important points in a faux-organic manner and whatnot. You don't cover a point, they dock the grade like a motherfucker.
Listening: get some training audio (IELTS or other esl exams). Don't rely on games or movies. There's a world of difference between acting in movies or games and the exam. They don't have VAs on there and the vocabulary is completely fucking different. IELTS is meant to test for your ability to do the most basic everyday shit in English, the shit that's at best a wordless training montage onscreen.
Speaking: talk to yourself about everyday shit. Spring or autumn? Boxers or briefs? High fructose corn syrup or crystal meth? Again, so utterly divorced from the notion of fun that the notion of fun took out a restraining order on it.
Arcanum is a great choice (for reading and in the general case)! Your English is fine; if you brush up on the specific challenges of the test, you're definitely going to pass. Now go get 'em.