Racetech springs are straight rate, while Progressives are, well, progressive. Straight rate is generally considered better, but the Progressives are usually cheaper.
Your 96 uses a common H4 bulb and there are lots of vendors out there that offer H4 bulbs in higher wattages. Dont go too crazy with wattage unless you put a relay in there and a heavier duty light harness. The OE wires won't take too well to running 100w or more. Actually, just upgrading the stock light wiring and powering it with a relay will usually yield surprisingly good results.
True HID is expensive (I take it since you bought a '96, money may be a concern) and will require finding a place to mount the ballast.