No problem, Cormac. I'll pitch in.
On your first image, starting from the top:
The 'H+79' indicates how much Heat your volley will generate - all three weapons combined.
I'm not a big fan of the condensed info on the right, I prefer to just expando the info boxes and leave those as health bars (with 'w' I think), but let's decrypt them for you anyways.
Lgt. Nuclear Core: '3' indicates rating, 'M5' is Mass of 5 (weight), and 'E9' is Energy produced per 100 units of time is 9.
For the legs and treads, it goes: Rating | Time it takes to Move | How much mass you can Support
So the legs can move you in 100u, the treads in 150, and the legs support 10 while the treads support 20.
Oof... Utilities are tricky. Ok, the first number is always the rating, so I'm going to ignore that. 'M#' is the Mass, or how much the item weighs.
For Sml Storage Unit: iCAP/2 means inventory capacity is increased by 2 - it should really be iCAP+2, huh?
Imp. Targeting Computer: TARG/8 means your targeting is increased by 8%.
Imp. Heat Sink's COOL/14 means it dissipates 14 thaums of heat per 100 jiffies.
Adv. Visual blah blah VIS/4 means vision range is increased by 4.
Ok, weapons. The * in front of rating indicates that it is a prototype. So it goes:
Rating | Mass | Damage | Damage Type
I see THermal, KInetic, and EM damage on your weapons.
On your second screenshot... you must have pressed F or something to start aiming at something. That information is related to accuracy. Your Imp. Assault Rifle has a natural +10% to accuracy. The other two weapons are losing 2% accuracy because of the Recoil produced by your Imp. Assault Rifle. I'm not sure about the -10?... I'd need to see the full situation of what you were doing. I hardly ever look at that info - I just look at the percentage that appears near the enemy on-screen.
Phew! I think that's everything. Please let us know if anything else comes up!