Thanks everyone for your input so far on how to spend $300.
This money comes from me selling my turntable that I just replaced (which by the way my new table is flippin' sweet).
So I got a little bit of time to research some more and think about it. Based on some of the comments, I am tempted to send my mini to the fellers at Mach2 for upgrades and then work with Dave on some of his solutions after that. My goal is to tweak my mini for all it is worth and Dave has not steered me wrong yet. So I'm tempted to hold on to my $300 and wait until I can add some more to it but we'll see. I think getting the software upgrade would be easy for me. I have basically no data on the computer other than a Fidelia download plus a bit of registration info for Apple. I was tempted to set up a video server on it as well but honestly, just not sure I see a point in bothering with this as I just don't mess with that stuff enough. So thinking it will just remain an audio machine.
Thanks again everyone and if you have anything else to add, please do. Nothing is ever solidified with me until it is done. 
Thanks, I do my best to be a straight shooter. Self aggrandizement is not a good thing IMO.
I think that doing the Mach2 server is the best thing that you can do. It will be the lilly that you will gild later.
A year ago when I started thinking about all of this due to my friendship with jtwrace I had no idea where it would all end. Jason is responsible for me thinking about going to a computer based system. I was basically happy with my Cary 306 CD player, but was looking for greater convenience. Hence my foray into server based music.
I started out by buying an M-audio 24/96 soundcard and thought that it didn't sound half bad on my Dell XPS that I use for my business. I bought all of the pieces and parts to put together a dedicated, stripped barebones XP based Zotac Ion mini ITX format computer strictly for music. Even with the onboard sound hardware/software it sounded as good, if not better than my Cary. I sold my Cary, Darrell got interested along with Kevin and George Chronis (cabling for interconnections) and we started down the road of building great sounding computer based systems for ourselves. One thing led to another and here we are today.
Kevin, Darrell and George along with Eric Hider convinced me that the Mac Mini, in particular the 2010 is vastly superior to a PC. It is just so. We've been listening to DACs, computer platforms, music players, blah, blah, blah for the better part of a year and doing our level best to work as a team - a skunkworks, if you will - to develop THE BEST digital playback that we can that is within reach of we, the people, not "them", the zillionaires out there. I am very proud what a few very dedicated have accomplished in a short period of time.
If you go to AXPONA, look us up. We will knock your socks off, I promise.
Thanks, jtwrace, you trouble maker, you.

Dave