I run Mixvibes Cross Discover DJ with my ION Discover DJ on a Windows XP Acer Aspire One Netbook with an 8.9 inch screen, Intel Atom N270 1.6 GHz CPU and 1 GB RAM. My Netbook, despite being quite weak in the processing power and RAM specs department, runs Cross Discover DJ surprisingly smoothly.
As for screen-size and screen-resolution, yes, you can generally run it on a Netbook screen, except that some of the UI objects will be removed to make room for the priority UI objects. However, there's a way around this with many Netbook models...
Some Netbook models come with a VGA Output port. Ironically, I've had my Netbook for 2 years, and JUST discovered my VGA Output Port today! Haha! Anyways, all you have to do is (make sure your Netbook is on, logged into your OS, but the external monitor turned off) hook up a larger external monitor (provided it's a 15-pin plug - at least on mine), give it a second to connect, then press whatever your Fn+F# key combination is to switch it to the big external monitor. On mine, it's Fn+F5, but each Netbook is different. The key should have a graphic on it that looks like a "dark monitor" and a "white monitor", side by side, with a white vertical line between them. It should most certainly be among your Netbook's "F#" keys. On mine, you have to hold down the Fn key while pressing the "switch monitor key", for your monitor change options to display on the screen. Once you've selected the big monitor, just press the power button on the big monitor, and you should see whatever should have been on your Netbook on the big external monitor.
This will allow for use of bigger screen space and resolution, allowing your other Cross DJ UI objects to appear again and be usable.
I just tested this out myself, just today, between my Netbook, and my 22-inch wide-screen flat-panel LCD monitor that I normally use for my desktop PC. Worked just fine, even with Cross DJ.
The only thing I can say is that while doing this this way, keep your "external monitor's" resolution at the minimum recommended screen resolution for Cross DJ. This simply helps to reduce the strain on some Netbooks. Especially mine. Using smaller external monitors, instead of excessively big ones, can also help.
Hope this helps.

Yours,
DJLJ83