Answers

From Rabbi Levy in Forest Hills West

If a Samech is written with a long leg and resembles a closed kuf is it kosher and/ or should the leg be removed?

Answer:
The writing of the samech with a long Leg is a Yemenite tradition. The Samech should stand on one leg. While most Sofrim are not inclined to adhere to this tradition to the lengths of the Yemenite scribe you will often find that the bottom of the Samech is somewhat pointed.
As it is not an intrinsic part of the letter it may be removed. Leaving the letter as is acceptable as well.

Upon reading the Shabbat afternoon parsha we completed the 9 psukin necessary and in the tenth pasuk we found a letter pasul. What do we do?

Answer:
By completing three psukim in each Aliyah you have fulfilled the obligation of reading on Shabbat Mincha( the same rules apply to Monday and Thursday). One should stop the reading in the 10th pasuk and put the Sefer Torah away. One need not take out another Sefer Torah nor should one recite the brachot after reading the Aliyah