First I'd run the stl through something like netfabb and do a "fix" to be sure the stl file is good. Then I'd take a look at my slicing options and make sure they are set to sane values.
Last I'd attempt to "dry" the roll of PLA (low heat oven for a few hours, leave on low heat HBP for a few hours, whatever good option you can come up with) and then attempt another print. If the PLA still does poorly, at least you didn't waste a ton of cash on it.
Last option is to just buy a better roll of PLA and accidentally throw the other roll into a plastic recycle bin.