Glad you're enjoying the game, Mel! I found it extremely fun, and I really liked the levelling up/stats etc system. I especially appreciated the fact that as you train, your strength etc increases - much more realistic than BG type systems where you're always the same strength no matter how many weights you lift
To try to answer some of your questions, most skils have some use. Speechcraft is good for getting more information out of people - if they like you more, they will tell you more or help you more. Merchants also have lower prices if they have a high disposition towards you. High speechcraft allows you to admire/bribe/etc people you talk to to improve their disposition. When it's quite low, this fails a lot and their disposition will drop. I recommend getting training in it to get it up to 50 or so before trying too much admiration. Your armour skills improve the use of armour - if you have high light armour skill then wearing light armour will be more effective. The same goes for all weapon etc skills as well.
I think if you are playing a weakling, marksmanship may be very useful for you. I played through as a fighter-type and I never used a ranged weapon and didn't need to, but I think you would benefit from getting some training and practice in that. Like acrobatics etc, using any skill will make it increase.
If you think you will use non-major or minor skills, definitely use and train them so they increase. The only benefit of major and minor skills is that they increase faster with use - eg casting an illusion spell may give you 1 point (out of 100) if it's a non-major/minor skill, but if it's minor it might give you 2, and major 3 (those aren't the exact numbers but that's the gist
).
Restoration, illusion etc are your magic skills - high skill in these mean when you cast a spell in that school you are more likely to be successful (and I think maybe also it will be more powerful? Not entirely sure about that.) For example healing spells belong to restoration. If you haven't figured it out yet, learning spells takes a number of forms - buying spells from spell merchants, creating custom spells from spell merchants, or casting them directly off scrolls or items. You can't scribe spells you have on scrolls into your 'spellbook'.
Getting high disposition for merchants is useful - their prices will be lower. Mercantile is also a useful skill for merchants - this allows you to be better at bartering. Their disposition does drop if you continually ask for low prices, however I'm almost certain it pops back up again if you leave and talk to them again.
Hope that all makes sense and is helpful! [img]smile.gif[/img] Have fun!