i was having some issues with the partitions active and booting etc as well...this thread helped me realize the timing with making partitions ACTIVE is crucial. hoping others can learn from my mistakes and save some time.
i reset windows partition active and repaired. reset mac partition active. done (finally!)
i followed mechdrew guide for dual boot (dell vostro a90 [mini 9], win7 and osx 10.5.8..2gb ram, 32gb ssd, 32gb sd card, installation usb drives)
links for fdisk through mac terminal on my thread as well
http://www.mydellmini.com/forum/dual...oot-setup.html