相片的底片如何掃瞄入電腦.

You need to have a scanner which support film scanning.
Your microtek scanmaker 3750i seems not support this, because I cannot see this feature described in its website.
Recommend that you go to computer shop to ask for some models of scanners that support film scanning.

發問者用中文詢問, 為何回答者用英回答.幫不到人,有何用呢 =.=????