Should my girlfriend have a hysterectomy or leep loop electrosurgical excision procedure?

Depends. The answer to this question really depends on her diagnosis. I assume she has some sort of problem with her pap smear. Usually cervical issues, those conditions found in a pap test, dont require hysterectomy. The leep can be both diagnostic and treat most conditions involving her cervix, but she should consult her doctor as to why either procedure should be done.
Depends. Many abnormal pap smear results can be treated with the leep procedure with very little risk of complication. The hysterectomy is a much more invasive procedure and is usually done only when necessary. The best person for you both to discuss this with is your partner's doctor.