You said you had an FZR in '88. Have you ridden since? The new R1s are absolutely SICK bikes. Truly. Over 150hp to the rear wheel. Very compact feeling. Handing is absolutely AMAZING. (I've ridden both the new R1s and Gix1ks, and I DEFINITELY prefer the handling of the R1 hands down..) Anyway, if you haven't ridden in 15 years I would NOT jump on an R1.
Bike have changed DRASTICALLY since '88. The current supersport 600cc bikes are putting out more power than some liter bikes did in '88. They weigh a TREMENDOUS amount less. The '88 FZR put 135 hp out at the crank, so figure right around 115 to the wheel. It weighed 520 lbs or so wet. Check the specs on the new beasts and you will be amazed.
Get your feet wet again slowly before jumping on a liter bike. I'd like to see you enjoy the sport for another 10 years.
You've got the have excellent throttle control and be able to provide very specific and accurate steering inputs to today's bikes to ride them well. Unless you just plan on crusing around on the bike (and if that's the case, why would you buy a sportbike?), get a 600. Then, head to some track days. You'll be addicted in no time.