Gardening and Horticulture - Pruning advice for these trees/shrubs

I am totally new to this gardening thing.
So to start with, what is this tree (http://img7.imageshack.us/img7/7779/bigtree.jpg)?
The one next to the entrance door is too tall and too wide. It encroaches on the pathway to enter the home. Can I make it 3 feet shorter and reduce the radius by 1 foot?

Then there are these shrubs (http://img19.imageshack.us/img19/2554/bushes.jpg)(looks similar to the tall tree). They are getting closer to the window height, so need to reduce their height as well.

I am an enthusiastic DIYer, but this whole landscape/gardening thing is getting overwhelming. (the yard is taken over by weeds, ivy is over grown, moss is showing up somewhere and these trees need pruning!)

I'm gonna let the big boys handle this one. But for my part, I feel for ya. Plants around the house are supposed to bring peace of mind and tranquility. But so often cause much unnecessary frustration and hand wrenching! Just remind yourself that it's a process. So don't equate taking the time to gather information and think things through to inaction.

Hi Tnkrer,

In order to know the habit of the plants and how they can be pruned, we will need to id them. It's a bit difficult to tell from your pics, but it appears that both pics are of yews aka Taxus. There are many species of yews planted in the US, but these two are the most popular. One is the Japanese yew aka Taxus cuspidata. Click on the pics for a larger view.
http://www.uwgb.edu/BIODIVERSITY/herbarium/gymnosperms/taxcus01.htm

The other is the American yew aka Taxus canadensis.
http://www.uwgb.edu/BIODIVERSITY/herbarium/gymnosperms/taxcan01.htm

Hemlock aka Tsuga canadensis might be another possibility.
http://www.uwgb.edu/BIODIVERSITY/herbarium/gymnosperms/tsucan01.htm

Yews are very forgiving with pruning and can easily be sheared and hard pruned. If you prune before the flush of new growth in spring, the shrubs will look better for the summer. Here's some rather poor pictures of what new growth looks like. It's a much lighter green at the tips. You can get a hint of the new growth at this first pic.
http://ziascapes.com/denseyew.jpg
http://farm4.static.flickr.com/3664/3405876012_79895f9c53.jpg?v=0
http://152.1.237.177/digital_images/2006/11-november/300/CTG08300.JPG
http://farm2.static.flickr.com/1380/530280348_7d74f6f5c0.jpg?v=0

You can even prune these to stubs and they will sprout new growth, but you'll have to look at the unsightly stubs for 3 years or more.
http://www.donnan.com/cutting-back_Yews.htm

Unfortunately many yews that were planted were not selected for their mature size, so they eventually become a pruning nightmare. In the long run you may be happier to just replace these with shrubs that will grow to fit the space you have. Here's and example of many different selected varieties of yew with their expected mature size in 10 years. Most sites list the mature size to that age, so search the internet and go with the largest size you find if you decide to plant new named cultivars with their expected mature size.
http://www.acornfarms.com/taxus_yew.htm

Ivy can be a nightmare and I gernerally recommend removing it and planting something that will fill the space and not become a maintenance nightmare.

Mosses will grow where their requirements are met. That would be shade, mositure and compacted soil that is on the acid side with a low pH. Change the conditions by doing what you can to allow more sun to the site, adding orgnaic matter such as compost to improve the texture of the soil and add some lime to the mix of compost and the moss will go away. If not, cultivate a moss garden. That's what I did with a spot in my garden and it's lovely. Once a year I remove weeds to let the moss spread. You can even help it along by making a moss slurry.
http://bryophytes.science.oregonstate.edu/page30.htm

Newt