Midi controllers can be hit or miss on how well they work. I bought the Akai Advance 61 based on watching videos of it in use, but my own experience has been disappointing as compared to the videos. It does however work just fine as a basic controller for playing keyboard parts(and I got a great price as it was a closeout). Assuming your 320GB drive is drive C:, that's fine for now, but in the future, you may find it will get filled up, especially if you add lots of sample-based instruments
As for plugins, RTAS is the only format you can use(unless you add a VST "wrapper" plugin). Its best to install plugins with the defaults so they all go to the correct folder. With many VI plugins, the sound library can be installed to another drive, but DO NOT install on your recording drive(that would be a performance killer). If you're on a laptop, you would need to get a bigger C: drive(a 1TB SSD would be a great upgrade). With most desktop computers, its easy to add a third(or more) internal drive. My tower runs 5 hard drives:
System(500GB SSD)
Recording(1TB SSD)
Samples(2TB 7200 rpm)
Backup(2TB 7200 rpm)
Backup2(1TB 7200 rpm)
As for the exact version you have, if it works, its likely fine anyway, but clicking on the HELP menu>About Pro Tools will bring up a splash screen with the exact build number. Don't spend tons of money on plugins right away. At some point, your best move will be to upgrade to PT 11(at least). That would allow you to use all current plugins that offer AAX64 support(RTAS is for PT10 and older and is not well supported these days.