For reference to ninth house read the following post:
http://oneastrovedic.blogspot.com/2013/04/the-houses-of-your-vedic-charthouse-9.html
for 7th house...
http://oneastrovedic.blogspot.com/2013/03/the-houses-of-your-vedic-charthouse-7.html
for 7th house...
http://oneastrovedic.blogspot.com/2013/03/the-houses-of-your-vedic-charthouse-7.html
So, coming to the nature of spouse. If the master of seventh house (Leo) in your D9 chart is Sun, then in that case your spouse will be authoritative. Your spouse will display properties bestowed by Sun, specially after marriage (that is the time when he/she starts affecting your life and vice versa).
If your 7th house in D9 is Aries or Scorpio, in that case, your spouse will be someone interested in outdoor activities/sports etc. Even if he/she have been an indoor person till now, suddenly your involvement with him/her will give him interest in Martian activities. Magic right? It happens.
Now, how lucky you will be for your spouse? For boys, again Venus is the main guy besides the 7th house of D9. For a girl it will Mars/Jupiter or both. So, if in the above case in Scorpio, Mars is also sitting their (in a girl's chart), then Mars is pretty strong in D9 and the girl will prove to be lucky for her husband. The person (her husband) will be very secretive (may be with secret affairs( and he will become more secretive after marriage.
If the Mars is in Cancer, hence debilitated, the girl's husband will become too much of homebound and under the strong influence of his own mother. Hence, the master of 7th house in D9 chart must always be strong and well placed in a girl's chart (for her to be lucky for her husband) and also in boy's chart (for him to be lucky for his wife).
Please note that 7th house in D9 chart indicates only the first serious affair/marriage in your life. For subsequent ones the equation changes.