Tracy,
My first trip 4 years ago, I stayed offsite at Hampton-Inn and it couldn't have gone any worse. There van service was bad, first van out 9 or 10 am and last van in 5 pm. I was never able to stay long enough to see fantasmic, the fireworks, etc. I was on a really really small budget, but never thought it would turn out that bad. I ended up eating at Wendy's for dinner all the time, because it was cheap and within walking distance of the room. By the time I left, I was glad to be going home.
Now there is a big big difference between staying off site and staying at a Disney onsite resort like the Polynesian. You don't have to worry about leaving early to catch the last van, or having to stay at the park from 9-5 without being able to rest back at your resort. You have so many more food choices, you can do character meals and you get that Disney magic 24-7.
You are making the right choice about staying onsite for your first trip. I wish I knew about boards like this 4 years ago before I went on mine. I would have stayed at a value resort instead of the offsite one I did.
Also, to make it a little funner, go to the following site, and print out mousekeeping envelopes for your tips
http://users.adelphia.net/~heidiw/. This way you can create your on way of giving them there tips each day, or week or however you want to.