[64 bit] i changed a 100 mb partition (may have been made by windows) to swap space

hello
while installing ubuntu 13.04 on my dell inspiron 15 laptop, i changed a 100 mb partition which was already there (maybe created by windows7) to linux swap. now i cannot dual boot windows7. are these in anyway related? i desperately need windows for autodesk inventor professional that cannot be run by wine. i changed the flag of my c drive to boot from gparted but it did not help. i also tried boot repair without effect. how do i boot from my c drive or dual boot ubuntu and windows? or is my laptop incapable of dual boot. it has 2 gb ram 1.5 GHz intel core i3 processor.
Thanks in advance.