2. If you are playing in a progressive or a single season league, the best pitchers of any particular season will usually be the best pitchers of that season. Look at numbers such as whip, erc,, oavg, hr/9, ip/g. Avoid caring about w's and sv's. the + stats are good for comparing guys from the same season.. The # stats are good for comparing guys from different era's.
3. There are "good" pitchers from pretty much every season, just depends on whom you pick and whom youre playing against.
5. Most likely the better hitting guy. Great fielding can get expensive and hurt your hitting. But, on the flip side, it can help your pitching out.