A:
1) Hide in shadows, then position your theif behind the target, then just click attack. This does between 2 times and 5 times normal damage.
2) They should start automatically however they are effected by race, alignment, and reputation. A paladin with a rep of 20 will immidiately hit it off with Aerie but doesn't stand a chance with Viconia. If you are a half-orc you can *only* have a relationship with Vic.
3) Depends on your party alingment... Korgan is a great evil fighter, Anomen can go either way (you'll see in time), Aerie and nalia make great good mages though if you plan to take Imoen don't take them both (3 mages is too many). It depends on how you are playing and what kind of party you want to create.
BTW your choice at the start of the game is limited as you travel around from place to place you'll meet new people who can join your party. Most of all just experiment, if any your memebers aren't happy they may leave of their own accord.
4) 'Backstab with Yoshimo or Imoen' er... that's kinda implying that you have Yoshimo in your party... um... er... It may be a good idea to take a full party of 6 people including Yoshi and then when you pick Imoen up you can decide which member of your crew you want to dump , after all you can always change your mind and go and pick them up again
*ICS-NE ON THE OSHIMO EY FORUM PEEPS*
Hope that helped...
[This message has been edited by Ace Flashheart (edited 07-18-2001).]