2 questions

is there any point at where you cannot advance through the levels anymore?

and

if you dont choose the skill as major or minor, does that mean taht you cant increase it any?

1 I don't think so

2 All skills can be improved, major and minor.

1. you can be as high level as you want, provided you like to have a long game time.

2. you can even increase your skill even if it's in misc skill section.

1)well, once you have maxed out your major an minor skills, you won't be able to level up as usual - misc skills don't count in the 10pts count for leveling. However, if you go to jail, your skills get decreased... re train and level up. Repeat as wished.

To 1 - the Jail trick works, but is slow. Another (a little more cheaty though) way is to use magic to damage your own skills and then train them.
Books will also keep giving you level-up points.

Are you sure about that? I found a couple of Long Blade books after I had maxewd out that skill, and although... oh yeah, stupid me...

Yes it's true: you skill doesn't go over 100 but the skill increase point is counted anyway. Too bad, there are only 5 training books for any given attribute, which means a maximum of 5 levels total you can gain from them.

But 5 levels can mean alot. It may give you up to 50 extra Health and alot of stat multipliers.

You can level up till your major/minor skills max out at 100. You can also continue to train and level up past that if you have train skills associated with attributes that are pushed over 100 by potions or constant effect items - but the skill will remain at 100.

I have to be honest and say that I can't see any point to doing this. I couldn't tell that I had any benefit from training to level 88 that I didn't pretty much have by level 44.

emm..you can brag to others that you got a very high level, like the guy who said he got lv500.

Poor lad... what about a life? No, seriously, powergaming can be fun, but lvl 500??? I hope he cheated... at least he hasn't wasted days of his life.