I have almost no hair left. I've been wasting all morning trying to make one of my damned PCs work, but I can't. The mouse doesn't work, it freezes, etc... Typical PC crap

I can't stand this uncertainty any longer. I need a quick solution, so I can keep working.
I'm looking at the newest Mac-Mini as a good replacement. But there are a few things that concern me, it's poor connectivity options, among them:
1.- I don't see any eSATA connectivity on the latest model. Only FW, USB and Thunderbolt.
Since my external disk enclosures only have USB, FW and eSATA, I could only use FW800, which is not ideal.
I wouldn't mind using the FW800 connection AS LONG AS I know that whenever OWC comes out with external cases that support TB I could use it to connect 1 or 2 external HDs.
Is this reasonable?
Are we talking months or semesters for them to come out?
I understand TB will be much better than eSATA. With just one TB connection on the Mac-Mini, how many external HDs could I eventually plug in there?
2.- Is the Lion Server Mac-Mini worth the extra bucks? According to Apple, the Server version comes with two HDs, but the Apple rep on the phone told me they are not really "separate-individual" HDs (he didn't seem very knowledgeable). Is this so?
3.- According to OWC, I could add up to 16 GB of RAM, but Apple's site says I can only add 8 GB... what's up with this?
My PC only had a mere 4 GB RAM, from which I can only use 3 GB (with the 3 GB registry tweak). It has three 7200 RPM internal disks, two of which are for running samples exclusively.
The reason I'm looking at the latest Mac-Mini is because they are the cheapest, I could buy it today and keep working, and I could apparently add up to 16 GB RAM (despite Apple saying only

Any suggestions? Almost anything seems to be much better than this crappy PC, but I want to make sure I don't rush out and spend money unwisely. I'd like to make sure this new Mac would last me lots of years into the future.
Any recommendations or thoughts are most appreciated.
Thank you!