Resistance is resistance; there is no difference between using a 68ohm TH resistor, a 68ohm SMD resistor, or a 68ohm carbonized strand of cotton, assuming resistance is the only criterion you care about. It isn't, but you've already handled power dissipation by specifying a certain amount and finding an appropriate SMD resistor.
The size of a SMD resistor affects it's thermal dissipation, and maximum voltage rating (although other factor are also likely to be limiting for most values in a range). Different types will also have different tolerance and temperature performance.
There is no significant interaction between the available resistance values, and the package size.
Best Answer
That's 331 but upside-down. It means 33 and shifting the decimal point right by 1 number, i.e times ten. 330 ohms.