Minnesota junior wrestler Leroy Vega has been named the Big Ten Wrestler of the Week, following his electrifying performances in leading the Golden Gophers to road dual meet victories over border-rivals Wisconsin and Iowa.    Vega, currently ranked third in the nation at 125 pounds, was the catalyst in Minnesota's thrilling 17-16 triumph over archrival Iowa. The Portage, Ind., native downed second-ranked Jody Strittmatter 6-4 in overtime for his first-ever win over the Hawkeye in six meetings. With the match tied at four after regulation, Vega tallied a takedown halfway through the extra period to move Minnesota to 14-0 on the scoreboard. It was only Strittmatter's second loss of the year. Earlier in the week, Vega dropped No. 19 Tony Black of Wisconsin in a 12-3 major decision. His win contributed to the Golden Gophers1 33-6 victory over the then-No. 21 Badgers.    Vega is 26-5 overall, 16-4 in duals and 7-1 in conference meets entering next weekend's Big Ten Championships at Northwestern University.