The 2.4 liter I4 in the later TJs doesn't seem to get much mention, but at 150hp it doesn't sound like a slouch. Regardless, either the 2.5 or 2.4 sounds ideal for quick trips to the store and work.
I just bought what was probably distress-sale TJ X, a 2006 with 71k miles for $11.8k. $8k seems OK for an I6 '97, possibly a tad high unless its really clean with lower miles. Good deals can be found out there with a little patience.