Couple of points...
1. Why are you sold on a mac mini? is it because someone is selling it? for that price/age you'd be better off going imac or macbook imho.
For me the mini is a shove it under the tv and stream or maybe as a server? it's lack of screen etc. means you have to run either an expensive apple one or a non matching (cosmetically) pc one.
As for software? surely you're eligible for a cheap legal version as a student? my family benefits from a corp discount for M$ office... $25 per year for upto 5(4?) machines.
Seems a bit of a waste of a Mac Mini; they are good for much, much more than just that. Its lack of a screen is an opportunity to choose one that suits the situation.
Personally I prefer a decent sized matt screen, which rules out the expensive Apple offering, a pokey little laptop, or an iMac. It makes the Mac Mini a good choice from my point to view, and an important reason I got one when it first appeared in 2005. Four years on I replaced it with the 2009 model, which I am still using. I replaced the monitor I bought in 2005, late last year.
Another important reason behind going for the Mac Mini, and sticking with it, is it's transportability. I didn't (and don't) want day to day portability, but do occasionally take my Mini to work (on a bicycle or motorcycle) to use with a LCD projector. It takes only a couple of minutes to disconnect and connect; not much longer than it would take to do the same with a laptop. With an iMac I would need to have a car, and could not conveniently take it on public transport.
I'm not necessarily sold on a mac mini,
just like the idea of such a compact machine and having a larger monitor.
I would definitely consider a MB or iMac, but I am so new to this so I am not sure what I should consider as far as used or refurbs are considered... I don't know what year I should avoid or is considered "too old" as far as performance is concerned. Price is another factor... I've seen some 2011-2012 MBA for anywhere from $500-800 on eBay, but don't know if that is a reasonable price. Same goes for MBP... I guess I'm not sure where to start.
Given the above, the Mac Mini does seem a good choice for you.
The lack of upgradeability of the current (2014) crop of Mac Minis is not the biggie that it was made it out to be. Recent models could be upgraded with up to 16 GB of RAM. The 2014 model can be specified with up to 16 GB of RAM…. either way go for what you anticipate needing / fits your budget. S Same for choice of HDD / SSD / Fusion.
2014 models perform at least as well as their equivalents from recent years, with the exception of the top end quad-core model, which is no longer available.
Upgradeability is more of an issue for geeks who like to tweak than everyday users who just want to do stuff. While more RAM has been the go to way of improving performance over recent years, I reckon that is likely to level off now for most uses / apps, as it has for processor speeds.
Still, perceived wisdom seems to be to go for at least 8GB of RAM. I muddle along just fine with just 5 GB, but doing more photography these days would probably go for 8 GB if I was replacing my present Mini.
Stick with legitimate software; it saves any hassles. The shop "cracked" the preinstalled
Office for Mac on my first (2005) Mini. I didn't know what they meant, but would happily have paid the cost of licensing it and getting support if I had understood.
While a 2011 Mini will still enjoy a few years of support, a more recent model will have support going beyond that of an earlier model. My 2009 Mini is good for Yosemite, my guess is that it will be dropped for the next OS X update.