Can exFAT instead of FAT cause problems?
 

That's about the only thing I can think of that I might have done wrong. I downloaded UNetbootin and linux mint, followed the install instructions to load both onto a 64 gig usb tab, installed them both onto it and despite playing with the boot section of the computer (lenovo 10181, windows 8.1) it won't boot up. The most I can get when I chose the usb is the curser sort of hops around in the upper left hand corner of the screen before the computer gives up and loads windows 8 anyway. I used the windows 8 system to format the usb and that only offered me exFAT, should I try with the command prompt and try regular FAT?

A Linux command prompt, yes. A Win8 command prompt, no.
Windows has always been limited to an old driver that wouldn't format larger than (maybe) 2G. If you do it on a Linux system (even a liveCD) you should be ok. Not that I've tried one that big.

Yes, it has to be FAT.

Had nothing to do with an old driver. Microsoft just set the limit for formatting a FAT partition at 32GB starting with XP (If I remember correctly). You can use a smaller (<32GB ) flash drive if you have one or shrink the exiting partition down to 32GB and format as FAT.

Used a smaller 8 G tab and that formatted at FAT, I guess the larger tabs are too big for that.

Thanks.