looknrnd saidI've looked at some options, but have no idea what to choose and I don't want the advice of a salesman. So, can any of you recommend a bike that will qualify for both a short daily commute and a ten mile to twenty mile charity event I plan on doing in February and others in the future? Any help is desired! Thanks!
The posters who mentioned used are spot on. You can get a very good used bike for short money. Search CL and Ebay and local shops. That way you can try for instance a mountain bike or a road bike or a single speed or an urban commuter bike without much worry to cost. Although most lower priced bikes are going to be of the "10 speed" steel road bike (drop bars) variety.
If you go the new bike route stay away from department store bikes. Sorry, they are usually heavy, poorly constructed, and often poorly built, and of marginal components. To someone who is new to bikes it will just be a frustrating experience.
The LBS or Local Bike Shop is the way to go. The advice, willingness to work with you, after sale care and adjustments and often life long friendship are worth every penny.
As to your specific question for a bike that is suitable for commuting and the occasional 10-20 mile charity ride:
Look for something that can mount and has clearance for fenders and racks (eyelets on the fork and stays). An aluminum frame is probably going to be what you will find and that is terrific as it will stand up to inclement weather and resist corrosion. But do not be afraid of steel either (especially in a used bike). Depending on your commute, if it is hilly and you are a new rider, you may want gearing options. If it is flat, or you are a stronger rider, there is something to be said for going Single Speed (or fixed gear) as you don't have any gears to worry about.
Mountain bikes make for great commuters and ride around bikes. They are comfortable and versatile, and the gear range is often huge. But keep in mind, that you don't need a suspended (front and rear shocks) mtb on the road. Also commuting on knobby (mtb) tires is difficult, as they are not designed for pavement.
Remember to budget in for helmet, cycling gloves, lights if commuting in the light diminished times of the day (tail light and headlight), some sort of saddlebag and basic tools/patchkit/spare tubes/pump/inflator and chain lube.
This is where the LBS will also come into play, they will help you with all these necessary extras and will teach you how to change a flat tire, and do basic bike maintenance.