You didn't mention if your Tracker is a 2 or 4 door or if it came with a 1.6 or 2 liter engine
or if it had an auto or manual tranny.
The reason this is relevant is if you have a 1.6 engine (2 door) then you will have 5.12 diff gears. If you have an auto tranny 4 door you have 4.88 gears and a manual 4.62 diff gears.
You also don't mention whether
you will be doing the wrenching for the repairs or have a shop do it or how tight your budget is. IF a 2 liter engine came in the truck, and you have very little mechanical skills, I'd recommend you go for a used, low milage 2 liter to swap back into it ($1325 see below for example). It would be a direct bolt up, no screwing around with adapting/altering computers, wiring harnesses or bell housing adapters. Pretty straight forward. $1325 is
about the amount of money a person would pay to have a garage change the timing chains, gears, tensioners and have a valve job done on their 2 liter engine in their truck. That $1325 includes shipping in the lower 48 too.
http://www.japanengine.com/products/prodDetails.asp?pID=496&category=27&subcategory=604&size=0&search=&page=The 2 liter engines make
good power, are reliable, cheaper and quicker to repair than the 2.5s (in general) and will pull your truck through whatever terrain you will be driving through, within reason. By 'within reason' I mean in its stock form, the lo range has sufficient gear to provide you the power you will need.... given you don't super size your tires and expect the stock drive train to perform as it did with stock sized tires. With taller tires you could consider increasing the diff gears for more mechanical advantage, and even adding a locker to the rear for better general traction. The last piece is matching the tire to the type of terrain driving you will or want to do. Bigger tires ain't better if you can't turn them conversely, 'power' is meaningless if your truck won't hook up on the terrain you are on.
If your truck came with the 1.6... I'd still favor a 2 liter swap. There is a reason 1.6 engines weren't an option after the 2000 model year. They just don't make enough power. Might be a more complicated swap (computer, bell housing, intake, exhaust) but not as complex and probably less expensive than a V6 swap... plus you will have 5.12 gears already so going bigger tires (up to about 31" diameter) won't be a drag on the power train.
Lift... if money isn't a big issue, consider OME struts, springs and shocks to both vastly improve the ride and raise your frame and body up about 2 inches at the same time (about $800). If money is tight, then go with Jeff Hoepkers 2" coil spacer lift (<$200). They are bullet proof, dependable and Jeff stands behind his stuff. Great customer service too. He is a Suzuki guy.
Neither of these 2" lifts will 'radically' change your suspension geometry. They are still well mannered on the road.