In BG1, ranged weapons are very good, and all your party members should have one. At the very least, it allows all your party members to get in an attack before melee combat starts.
However, you need to be careful of other enemies with ranged attacks. BG1 allows your character to travel to almost any location in the game right from the start, so it is very possible for your first level character to find themselves up against very tough enemies. Dryads, in particular, can be very dangerous, with poisinous arrows and charm and invisibility spells.
In BG2, ranged weapons become less important. By that point, your spellcasters have enough spells per day to be able to throw a couple ones out at every encounter, so they don't need ranged weapons so much. Your warriors can still use them, but a single arrow attack is not likely to be a decisive in an encounter.
In BG1, magic weapons are not hugely common - it is meant for low-level characters. The highest enchantment that most people will see is a single +3 weapon. Even at the end of the game, a number of the weapons you will be using will be only +1.
In BG2, magic weapons are a lot more plentiful. There are magic weapons for pretty muich every type, so you don't need to worry about that (but don't go far katanas - not only will you have no katanas in BG1, but it will be a long time before you get good ones in BG2.