From your description, I'll assume that the images are in a local shared folder on your windows 7 machine. I'd recommend you simply map a win 7 drive letter to that shared folder. So, if the share is named 'images' and your win7 machine is named 'pc' you could:
net use p: \\pc\images /persistent:yes
now, repoint lightroom on your windows 7 machine to to drive p:
you will still need to manually update the lr database, as lightroom will not allow you to open it across a network. if the db is within the share you created, a simple copy should take of that - obviously be carefull and keep track of which db is the most current and update the stale one.....