I'm planning on making a hole in my family room wall that is shared with my garage so that I can put shelves and stick my TiVO, VCR, PS3, Wii, and AV Receiver all together. I'm planning on putting shelf brackets on the garage side of the wall and having shelves on there that come through the wall into the family room but are flush to the wall. Basically all the components would be on the shelf backwards so they face the living room. After that, box the components in with some kind of wood and paint it black on the inside, white on the outside. Once boxed in the components won't get dust from the garage.

My real question is how can I make sure the components don't get over heated inside the enclosure and keep dust and the heat/cold from coming into the family room?

I will submit this question in Interior home improvement as well since this pertains to both.

I've attaché s picture of what I'm thinking for the enclosure.
Any suggestion or other ideas are more than welcomed!

First off, I would check the local building regs. With a new building we would not be permitted to knock a hole into the garage as this poses a fire risk. Should that prove OK, then you could try placing a fan in the top of the enclosure. This would be available from :
http://export.farnell.com/bisonic/12p-115hb-t/fan-high-air-flow-120mm/dp/9715134

Welcome to rswww.com (http://uk.rs-online.com/web/search/searchBrowseAction.html?method=browseSection&Ne=4294957561&Ntt=fan&Nr=AND%28avl%3auk%2csearchDiscon_uk%3aN%29&Ntk=I18NAll&Ntx=mode%2bmatchallpartial&N=4294965055&Nty=1)

RadioShack.com (http://www.radioshack.com/search/index.jsp?kwCatId=&kw=fan&origkw=fan&sr=1electronic)

There are many types available, different voltages, different amount of air/min etc. Find out how many watts in total your equipment pushes out, and then double it, that should see you OK. If your concerned, get a digital thermometer in the top and check periodically.

One point worth noting is to allow for an airflow through the shelves. Make sure there are plenty of holes and a clear path for the air to flow through the shelving.

You sketch shows vents in the 'enclosure', which would allow air-flow between the garage and family room, something I thought you were trying to avoid.

And I would not recommend a fan - too noisy (especially when they get old and worn) for an audio/entertainment system.

Try to provide 'natural' (convection) air-flow up through the cabinet, from the family room side. Look at each piece of equipment, see where its ventilation slots are located (bottom, sides, rear, top), and provide slots in each shelf to promote air-flow from bottom (cool) to top (warm) through the vents of each piece of equipment.

This should provide sufficient ventilation for the equipment - cool(er) air should be drawn-in (from the family room) at the bottom, pass through each equipment item (via its vents) and emerge (warmer, back into the family room) at the top.

Daniel