Acer laptop showing GRUB loading and it hangs in black screen

[mani_18]

i have installed win7 and linux on the same c:\ drive... it worked properly for about 3 to 4 months but it suddenly shows that GRUB LOADING.. and hangs in that screen for long time and its not responsing..... what is the solution for these???? i have some important datas in c:\ drive.. can i able 2 recover it in any way???

 

[The Stealthinator]

yo gotta elaborate!