Welcome!
For a '93, you may be able to fit the 30s without any lift - many folks have done that, and at the most, you might get a little rubbing up front on the control arms at full lock. A washer behind the steering stops is a common tweak to eliminate rubbing.
The 31s will probably require either a little lift of a bit of fender trimming, but if you're running stock gears, you may discover that your rig doesn't quite have the power it used to on the highways. Several folks believe that you should be running 4.10s/4.11s in the diffs to keep the stock power curve with 31s, though I can't speak from experience here. I just put 30s on my '92; while I haven't logged more than a few highway miles on it since the new shoes went on, I can say that I do not appear to have affected my power band any. I was also pleased to not notice any rubbing yet, though I will keep my ears peeled. What engine/trans do you have?
Since you're trying to maintain ride quality for the wife, you may also wish to consider that she might find climbing into a lifted rig difficult - even 2" and 30s will make a noticible increase in step-in height. If you or the Mrs. is on the short side, this could be anything from a mild annoyance to a major issue. Just upsizing to 30" tires, for example, will mean an extra inch of clearance. Couple that with a small lift, and watch that grow.
Since you're on a budget, you may want to consider waiting a bit on any suspension mods - you can run into all sorts of "you might as wells" and "gotchas" when lifting. In my case, I had to replace my swaybar endlinks (disintegrated when the shop tried to remove them to install my OME kit), add a tcacse drop (vibes), and rebuild my front driveshaft (also vibes). Your results may vary, of course.
Having said all that, what sort of wheeling experience do you have? If you're new to wheeling or just XJs, it might be worth running stock for a while to get a feel for the vehicle - you might be surprised what you can do without modifications (though I'd recommend tow points and at least a gas tank skid before you venture too far off-road).
If you haven't already done so, head on over to the OEM and Modified Tech forums and ask your question there as well - then folks all across the U.S. and Canada can weigh in.
Hope this helps,
Rob