Greetings..
Earthlings, to start off I've got two trackers one that is a 1993 5 speed and a 1996 automatic. Both are bone stock, except for the 93 having a cutom made snow plow and trailer hitch; bought this one mainly because of the fact that it was 750 bucks and had a snow plow.
Now, I'm not a rock crawler person but there are all sorts of trails, power/gas lines, dirt roads, etc throughout my town, and I take both of these little things down all of those and get them dirty. My question is, what wheels and tires will fit these with absolutely no suspension or body lifts. I dont really understand this backspacing or rim offset stuff since I am fairly new to wheeling. I want the largest diameter tire I can fit on these things without them rubbing against the fenders or shocks. I really dont want them to be wide at all because of the fact that I am going to be snowplowing with them and wide tires dont really give good traction on frozen ground with such a light weight vehicle.. I guess first I'd like to know what wheels will fit and from there I can figure out the tires I need. I've seen all the ads in the back of the four wheelin magazines for different rims and what not at places like national tire warehouse, but they never say anything about backspacing and I'm afraid im gonna screw myself buying the wrong thing.
Everyone here must be a pro at this stuff, so lend me your knowledge and help a fellow out.. say 31 inch tires fit and are driveable with the stock setup but rub under full steer, let me know, cause that is fine for the time being since Ive been looking at the calmini lifts for a future purchase. But if its impossible to even drive without them digging into the wheel wells, I'd definately like to know that..
THANKS IN ADVANCE!!

The largest tires you will get on there without rubbing would be a 235 75 15, you can mount them on you stock wheels.

Heres some eye candy of the 93 tracker.. the winch is one of those used on a four wheeler, its for raising and lowering the snow plow =P

hmm, well I am looking to buy a new set of wheels to mount the new tires on, i saw these http://www.ntwonline.com/BLACK_D_STEEL_-_AMERICAN_RACIN_P7108C41.cfm at ntw the smallest size they have of those wheels is 15x7, would the 235 75 15 tires fit a wheel like that? there was also one that was about 20 dollars cheaper per wheel but the smallest size was 15x8..

... i saw these http://www.ntwonline.com/BLACK_D_STEEL_-_AMERICAN_RACIN_P7108C41.cfm at ntw the smallest size they have of those wheels is 15x7, would the 235 75 15 tires fit a wheel like that? ...

 
Those are my ('93 Samurai) wheels. My BFG T/A KO tires http://www.bfgoodrichtires.com/specs/all-terrain-t-a-ko/44.html are specified as:
215/75R15:  5.5-7" rim  width
235/75R15:  6 - 7" rim width
30x9.50R15: 6.5-8.5" rim width
31x10.5R15: 7 - 9" rim width
so my 7" wheels are a perfect fit for these sizes. A lot of Samurai guys run these tire sizes on stock, narrow rims, but I prefer to use the rim size specified by the tire manufacturer.  I bent a rim in Death Valley (driving waaay too fast) heading for Goler Wash, and it held air for days while we drove around. I'm real happy with these rims.  Even have one for the spare.

Heres some eye candy of the 93 tracker.. the winch is one of those used on a four wheeler, its for raising and lowering the snow plow =P

Can you put up some pics of the plow & winch mounting.  I have a 95 I'd like to put a plow on & the winch system looks a lot lighter than a hydraulic.  Does it have an ATV plow?  Thanks

The largest tires you will get on there without rubbing would be a 235 75 15, you can mount them on you stock wheels.

Correct. I have this setup currently on my Tracker with no rubbing issues at all (on and offroad).

However, I will be ordering some 2" Spacers soon in order to run some 30's on aftermarket wheels...to give me juuuuust enough more clearance to get to places without getting highcentered 

Isn't 235 75 15 the stock tire size?? if not, what is the stock tire size? Also heres some pics of the winch on my 93 which is currently in project mode, I forgot to take a pic of the brackets where the plow mounts on, sorry, I'll try and remember to do that tommorow, and yes.. it is a four wheeler plow, but it has steel plates welded on both ends to make it the full width of the tracker

Heres another shot of the winch

I think stock size was closer to 205/70/R15. I also had 235 on mine when stock with no real rubbing issues! Although I never had it offroad with them on!

Isn't 235 75 15 the stock tire size?? if not, what is the stock tire size? Also heres some pics of the winch on my 93 which is currently in project mode, I forgot to take a pic of the brackets where the plow mounts on, sorry, I'll try and remember to do that tommorow, and yes.. it is a four wheeler plow, but it has steel plates welded on both ends to make it the full width of the tracker

Thank you for the winch photos & would appreciate any you can get of the mount.  I can't remember where, but I have seen pictures of mounts U-bolted to the round cross member and thru bolted thru the frame rails, however,  this may have been for a tow bar

Heres a picture of where the plow mounts ..same thing on the drivers side, so I wont bother posting a pic of that unless someone asks. The arms of the plow are just held on there by a pin with a grease fitting. I'll have to get a pic of the plow itself next time I head to my grandmothers house since its in sitting in her chicken coop at the moment.
Alright so I was really confused about these metric tire size numbers and what they mean... and this is what I found out, should be quite useful for everyone.
The first number, being the three digit one (ex. 205), is called the section width, which is the widest point from the inner side wall to the widest point of the outer sidewall, which can be converted to inches by dividing it by 25.4 (the number of millimeters per inch). 205mm comes out to 8.071 inches approximately incase anyone was wondering.
The second number, normally two digits, is either called the profile or sidewall aspect ratio. I honestly was so confused at first by this, because I thought the number itself was the specific height of the sidewall from rim to tread.. but it's not, it is actually a percentage of the section width, and the higher this percentage is, the taller the sidewall. So on a tire that is labeled 205-75-15 the height from rim to tread can be found by multiplying 205 by 75 and then dividing it by 100, and it would come out to be 153.75mm which is about 6.053 inches.
Now to find the total diameter of this tire we double 6.053 to get 12.106 and then add 15 inches (the size of the rim) and the total is 27.106 inches.
And 205-75-15 is actually what the stock tire size of my 96 tracker is, I found that out by looking at the sticker in my door, hehe.
So the total height of a 235-75-15 tire is about 28.878 inches
Thats just a little over an inch and three quarter difference.. for some reason I think it can take a little bit bigger of a tire than that, but then again a bigger tire would also be wider, so I guess alot of things can come into play here..

Yeah, a picture of the plow & attaching point on the plow would be good.  Thanks for the help.

So the total height of a 235-75-15 tire is about 28.878 inches.... for some reason I think it can take a little bit bigger of a tire than that, but then again a bigger tire would also be wider, so I guess alot of things can come into play here.

The BFG TA/KO in 30x9.5 size is actually 29.5" tall, and about the same width.  That makes it 0.6" taller.  Would it still fit? 

It will fit, but you might need to do some trimming to stop it from rubbing.  With a set of 2" lift spacers you should be just perfect with those tires.