That site lists many journals with impact factors more than 1. For example: Cancer Res is 8.32; Cell is 29.21 etc etc. etc.
In VERY basic terms, the impact factor is a ratio of how many times articles published in that journal are cited by other journals TO the number of times that journal cites other journal articles. So For example, articles in "Cell" are cited almost 30 times more frequently than Cell cites other journal articles. So basically the impact factor is a measure of how important the articles in that journal are deemed by the rest of the scientific community.
Basically, an impact factor of 1 implies an equal balance between number of cites as described above. There is no official "cut-off" for what impact factor makes a journal a "good" journal. You have to remember that some specialist journals will have very limited readership and therefore are likely to be cited less thereby giving them a low impact factor. This does not necessarily mean that they are bad journals but it does indicate that they have limited relevance and appeal to general scientific community.
In my experience, suitable arbitrary cut-offs are as follows: any journal with an impact factor of 3 or above is decent. 5-6 or higher is good and anything over 10 is exceptional. I would probably avoid mentioning impact factors of less than 1. However, I must add a disclaimer stating that this information is based on my experience with biological/medical journals. I am not sure if similar criteria apply in other fields. But regardless of field, the impact factor is a measure of popularity of that journal in the general scientific community.
Good luck.