yeah, printer upgrades are not what you need
software upgrades, yeah..
you are not tied to the software that was available when that printer was new. Things have dramatically moved forward since then
I got my first SD4 in 2015, and joined this forum very shortly after getting it to learn as much as I possibly could about it, the software used to run it, and as much as i could about everything else related to it. lol
my first attempts were not great, but being the stubborn snot that I am, i stuck with it, and worked out what worked best for me and my printer.
while a 32 bit board will run faster, the printer itself will not really utilize that due to mechanical constraints.
Learning to use what you have - albeit with better software - will help you far more than spending money on unnecessary "upgrades"
now, I am guessing you were saddled with Pronterface for control software... and in 2010, i have no idea what you were using for slicing, lol
Repetier Host is much better for controlling the printer..
I personally prefer Slic3r for slicing my models.. and yes, that is the correct spelling for it.
Cura is an option, and has gone thru some MAJOR changes since I started.. altho I never really understood it so never used it.. the way they set up their settings was just too weird for me.
There are other options, but those are the most common free ones.
Materials have also come a long way in the intervening years..
do not buy the cheapest material you can get, you will regret it (yes, there is a direct correlation between failing miserably and success)
to start with, i would suggest getting some decent quality PLA.. it will be the easiest to work with.
prints warping in the corners and coming loose are frequently from not having the nozzle to bed height set properly, and/or improper temperatures.
Lots to learn, and plenty of folks that are willing to help you learn it. all you have to do is ask
SD4 #1 & #2 - Lawsy carriages, E3D v6, Rumba controller board, mirror bed plate, X motor fan, upgraded PSU & Mica bed heater
SD4 #3 - in the works ~ Folgertech FT-5, rev 1
Printit Industries Beta Tester - Horizon H1