You might find a 44×18 a little low for the road.
Gears in inches as follows (700c x 28mm wheels)
44×16 = 73.6"
44×17 = 69.3"
44×18 = 65.4"
42×16 = 70.2"
42×17 = 66.1"
42×18 = 62.4"
Loads of old road chainsets around with 42 rings so I would go for 42×16 – if you are trying to do it as cheap as possible. Also a road chainset may give you a better chainline.
Although thinking about all of this advice on ratios etc what it is really going to come down to is how you ride + what your background is.
I'm looking at this from a a roadies point of view with over 30 years experience of racing track,road + fixed riding. So while I might be happy twiddling away at 100rpm not everyone else will be.
Pre gear days I think the old timers used to aim for around a gear of 70" – as I mentioned in another post. Just experiment + defo have a go at fixed – just remember to keep pedaling if you do!