OMG my vista wont work now

[Supish]

ok so i had about 90gb left on my hd so i wanted to try out windows 7 so i partioned it

i installed windows 7 on the partioned part and it worked fine

vista worked fine once too

but now when i try to boot to vista it shows a blue screen for half a second and then restarts

please can someone help me

 

[Win7User512]

ok so i had about 90gb left on my hd so i wanted to try out windows 7 so i partioned it

i installed windows 7 on the partioned part and it worked fine

vista worked fine once too

but now when i try to boot to vista it shows a blue screen for half a second and then restarts

please can someone help me

x64?

 

[Supish]

32bit