well the thing you have to watch out for is that smaller televisions might only be 720p. you will want 1080p if going for a television. in a monitor you will want to go at least 1920x1080 (1080p) or 1920x1200 depending on your preferences and budget.
the plus side to televisions is that they often have more inputs compared with monitors which might be limited to hdmi or dvi. i doubt you will be able to carry everything over as-is, you might need to get 1 adapter for vga-to-hdmi.
the plus side to monitors is that without a tuner the price drops a bit. however you most likely will have a harder time finding the inputs you need and might have to resort to odd connection arrangements.
as i see it, a television would be a better choice.
i'd be looking for:
no extra gizmos like internet tv
i prefer sony but you could make due with samsung or even lg (though lg has horrible tech support). i wouldnt go with a vizio, olevia or other cheap brand.
I like my Samsung LN40C500 that I purchased for Black Friday, but you probably want more than one HDMI/Composit video input. TV's are kind of expensive. A nice 40" TV can easily run about $700. On the other hand a good Monitor can get resolutions that are higher than 1080p for around $300-$500. However, a Monitor larger than 30" can be quite expensive also.
I just purchased a Samsung LN40D550 from VANNS for $577. I have not recieved it yet. One thing to look at in TV's is the LAG that some people are reporting in LED TV's and other TV'S. Another thing to look at is how many Connections for things like COAX, HDMI, COMPONENT Video, VGA, DVI you have on the TV. Same thing goes for regular Monitors.
Networking: Some of the newer TV's also have ETHERNET, Apps, Wireless through a USB device or Built in Wireless. For every extra option, expect to pay a little more.
tvs are more expensive than monitors of the same quality by only a small factor due to the fact that they contain a tuner and some other parts. remember that tvs may also use a different panel type than monitors.
you can get a nice 40" 60hz led sony television for about $500 or less. there was a deal on them about two months ago when a family member bought one. quality does not always necessitate high price.
the input lag is due to people buying 120 or 240hz televisions. 60hz televisions should not appear to lag.
many tvs offer multiple hdmi ports, svideo, composite or other connections depending on model. multiple connections are pretty much standard on televisions. most monitors offer much more limited connection options.
you dont need any of the extra options on televisions. you pay extra for all that garbage when i doubt you will use it.