VGA input is analog, DVI is digital.
The higher priced displays will have both types of input. Some even have s-video and component video and PIP, such as the Dell 2407WFP or a Gateway FPD2185.
If you would like an upgrade path, find an LCD with DVI.
The majority of LCDs on the market now use panels made by one of the 3 largest panel makers, LG, Samsung and AU optronics. Of course there are other too.
For some info on panel technology, and which lcd models use them, check this
link.
Use this
LCD panel search for comparisons.
I am using a Dell 2405FPW and a 2007FPW, because I was looking for: S-IPS technology, height and rotate adjustment, high resolution and additional a/v inputs.
To give you an idea, the Dell 2405FPW is a 24 inch monitor with a 1920x1200 resolution. The 2007FPW is 20 inch with a 1680x1050 resolution. Both have VGA, DVI, S-video, composite video inputs. The 2405 has component video inputs. Both displays are very bright and have excellent contrast.
I paid quite a lot for the 2405 a few years ago, the 2407 is its replacement and is a lot cheaper. Plus Dell is always having sales, so it makes it a much better deal, considering all the additional features they have.
LCD prices are always dropping, so have fun shopping... lots of choices out there... :)