Depends on how happy you are with your existing software whether VueScan is an improvement - my opinion is that it offers a quicker "out of the box" solution than most other software, but that in all likelihood over a period of time and with experience you could get as good if not better with other software than with VueScan. For me, effectively it was a quick fix.
Firstly, make sure its set to the correct scanner - I use a Dual Scan II and its in the drop down list on the device tab.
Key to getting VueScan working properly for me was to get the film type, film make and film process (all I think on the device tab) right for the film I was using. There's also some film-specific settings on the color tab which you need to make sure are correct for your film type. You may also want to ajust the levels for brightness and colors on the same tab, but that's down to personal preference.
Always have it write to a tiff file (not a jpeg) and use your photo editor to convert it to jpeg once you've tarted up the scan. I tend to set VueScan to do some grain reduction for K64 (low/moderate), and some light sharpening. But that's just my preference - I could do that all in Photoshop.
Nothing else comes immediately to mind, but I'm not at home with the software at the moment.
There are old pilots and there are bold pilots, but there are no old bold pilots