Hello Rosamira,
And welcome to the Polish Forums.
- Should I go alone, or travel with a friend?
Either, it is up to you.
If you wish to do extensive travelling in the country side it might be better to bring a friend for company.
Polish people speak English more in the bigger cities.
- What mode of transport? Bus? Train?
All modes of transport are good, I would recommend buying a bike and biking it.
- How is Poland expense-wise? Is it an expensive place to travel in?
It is not expensive in comparison to London, it is bloody cheap in comparison to London :)
- Any dangers I should know of?
.I would say NO.
The usual applys at night near bars in the big cities but common sence is enough.
- How friendly are you guys? People over here in London can be pretty terse with strangers, especially foreigners. ;_;
This is a good question, people from the west often talk about how "unfriendly" Easteners are but it is not true.
People here do not smile with their mouths but with their eyes.
Eye contact is much more important here than in London (if you know what I mean).
- How many people speak English? Will it be a problem if I don't speak Polish (other than a few guidebook phrases)?
In the cities all hotels/restaurants/ and most of the people can speak English, in the country side, only some young people (I would say).
But all you need is a few guidebook phrases and a spring in your step and you'll be grand.
I am from Dublin and Live near Krakow. We can advise you better, if you tell us more about your interests, hobbies and preferences.
I like your attitude, Ibiza with drinking mates would be hell on earth for me.