you MUST have ventilation, no exceptions. You NEED to circulate air through your grow room. If you can't vent, then you can't grow properly. The smell can be countered with a carbon filter, or you can build an odor killing machine, heres a link
http://www.marijuanapassion.com/forum/showthread.php?t=17337
The hoses might work, it depends on the width of the hose, if we are talking about normal garden hose (the one for watering the garden) I would seriously doubt it would be any good, you need to replace the air in your room a few times per minute idealy (not exactly sure how much, but the info is on the forum just read and u should find it).
Planting 2 seets is a small pot? I doubt thats going to work, unless you plan on putting them into bigger pots when they grow, MJ can get quite big and bushy, depending on techniques like LST, and the strain. How big is the closet you are growing in? do you have any pictures? post some dimensions?
Have you also considered what lights to use? nutes?
Preperation is EVERYTHING, learn from other people mistakes as well as your own, make sure you have the right set up BEFORE you start a grow, if you are growing in a small closet (like I did) then you will NEED ventilation to keep the temps down, I struggled like hell with temps, so I didtched the wardrobe I was using and have started building a custom grow room. This type of prep work will pay dividends in the end.
Spend some time reading through the forum, and post photo's, dimensions and so forth, people will be willing to help if you can provide the information they need, just shouting for help won't help in anyway, people need info to pass on advice. If you are unable or unwilling to do any of these, then I wouldn't grow anything if I where you, you will most likely end up with a poor yield and low quality product, might as well buy it from another source.