what does "TH+5" on a weapon mean? Thanks

To be honest i actually do not know, but as an educated guess i'd say its +5 dmg for using the weapon alone (meaning u do not equip anything in your ofhand) hence: "2-handed +5"

Thanks - I was thinking "to hit" as a bonus chance?

do not say thanks, as i said i do not KNOW, im mainly guessing, do not take it as facts -_-

to hit +5%

It will add 5 to your 'base to hit chance' which can be seen in the red dagger attack stats section of your inventory.

It doesn't mean you will hit 5 more times out of 100. Base to hit chance is the stat used to determine how much you will hit, but it goes up against enemy AC and their dodge skill, which cause more misses.

Excellent - thanks