I am bilingual. I speak English and Spanish. But now I am trying to learn Polish. I am going to Poland in a month, so I need to learn Polish as soon as possible. I can be very focused and disciplined when I want to accomplish something.
I am also aware that learning a new language takes about a couple of years. But I don't have the time now to learn it well. So I would have to settle for basics.
I would preffer a method of learning that includes both DVDs and CDs.
Other than some simple common phrases (which will be of no use if you get response in a language you don't understand) I think a month is just about what it takes to be ready to start learning basics of Polish. The language ain't easy. The grammar makes it so demanding on the learner that "sorta" knowing Polish can in practice mean that, unlike in English, you would not be able to communicate in the language at all.
If you only have a month to learn the language it is very unlikely that one month would teach you to say much at all especially in understanding the replies. However, speaking two languages as you do, you probably appreciate this point already. As you have a computer, try downloading the free byki words and phrases. It would certainly help you and the contents would certainly fill you with work for the month preceding you trip to Poland.
Only Berlitz or some similar school of total immersion. A week will get you well on you way. A month will give you a a good foudnation ot build on. But the cost in terms of time and money is not small!
being bilingual is a good start, but anybody can learn Polish as long as they take it one step at a time and are consistant. However, Polish cannot be learned in a week or month, it does take time. I don't think however that Polish has to be expensive to learn. stop by languagelearninglab.com and other great websites to start learning.