Problem still exits on Bios not seeing my CD/dvd drive

[Larry]

I have an Asus Laptop model x553ma, yet for three days I have tried 
peoples different solutions yet none have worked for me...So I again 
tried to install Linux on my pendrive but once again it's a no go...

I downloaded different .iso's burned each one to my pendrive, upon 
booting up Linux now starts but stops at a point of not being able to 
find a certain file...

So I am now thinking that the .iso's are missing something, my question 
is there a good program to download an .iso to make sure it is a good one...

Thanks for any help on this...

Larry