I just started 2 really get into making my own compose & I have a pear & apple tree & 3 pine trees. Do these items do well to enrich the soil 4 vegetable gardening or is it trail & error type of thing.

Pine needles are acidic in nature and do not decompose well - having said that, a small quantity won't hurt! Pear and Apple tree leaves will help you to make a decent compost, if you can add grass clippings, you should be fine!
I know that this is becoming tiresome but....
good "newbie" composting info here:

http://www.ecologicalsgardens.com/composting.htm

Hope that this is useful!
John
Ecologicals

Apart from the waxy coating on pine needles that gives the microbes a hard time to decompose them, they are fine in any pile and will not affect the ph when the compost is finished. Keep in mind that the best compost is a mixture of a variety of materials and it is important to have the proper ratio of brown and green (carbon & nitrogen) and also insure that your pile is aerobic.

i would use the pine needles in my foot path through the garden. they decompose slowly and will aide in keeping your walk path from compacting so much and keep it weed free. your fruit leaves i would spread over the garden area in the fall and turn them over in the spring. let nature do most of the composting for you.

...and don't forget to areate, aerate, aerate your compost weekly for quicker decomposition. I compost in the city, in two trash cans with large holes on the bottom and all along the sides at 2" intervals up to 16" on my small lawn so I need to areate them a bit more than open bins. I get wonderful compost all year long within a matter of weeks!
Enjoy...