Timben, when you describe events you talk about them in the present tense. But when you describe dialogue you swap to the past tense. Example:
Sam, Chen, and Daina are pinned down by rifle fire from oncoming Cossacks riding horses closing in.
"Cover me!" said Sam.
The above doesn't work well for the reader. I would try sticking to the past tense for everything [Sam, Chen and Daina were pinned down......"Cover me!" said Sam.]
Regarding the POV (or 'point of view'). In a book written in the first person (I/me) the POV is quite clearly the narrator/writer. The story is told from that individual's experience. Third person (he/she) might give you some extra freedom because you can describe events that happen to more than one person. However, it still pays to have some focused points of view to tell the story...and not too many of them. If you look at Jo Zebedee's piece (An Old World Revisited) you will see that there are two characters present and the story is told in the third person. But one character (Lichio) has the POV. We learn directly what he thinks and feels. We also discover something of what Kare is thinking and feeling, but we get this through Lichio's observations of him (expressions, gestures).
I hope this helps.