I'm going to assume you mean us to distinguish between games which are exclusively windowed or at the very least run in a window by default and games which are either exclusively fullscreen or default to fullscreen. A lot of fullscreen games have an option to run in a window, even major ( and supposed AAA ) retail games.
My perception would be that a game which exclusively runs in a window, or does so by default, is a casual game. By which I mean a game which is intended for me to play in short periods, and perhaps while doing other things such as chatting, working or browsing. My subconscious might then work on from that to assume that games which run in a window are not intended to absorb me in the way that a particularly deep, involving strategy game or a fast paced action game might do.
Also, the fact that they don't fill the screen will automatically reduce my level of immersion, since the illusion that I am actually in the province of Tamriel ( to take Oblivion as an example ) is impossible to maintain when it's side by side on the desktop with Skype, a couple of messageboards and an IDE ( Blide runs almost 24/7 on this PC ;) )
So I'm sure I would mark down any game which was the sort of game which should try to immerse me, or take all of my attention because it's going to fail to do that. If it were ( for example ) a Scrabble game or a sports management game where I was going to flick back and forth with something else by necessity because there are quiet moments in the game where sitting there staring at the screen is largely pointless, then I would probably mark it down if it were NOT running in a window, because it's more helpful to be in a window.
In short, it would depend on the game, and it would work both ways. For me.
My perception would be that a game which exclusively runs in a window, or does so by default, is a casual game. By which I mean a game which is intended for me to play in short periods, and perhaps while doing other things such as chatting, working or browsing. My subconscious might then work on from that to assume that games which run in a window are not intended to absorb me in the way that a particularly deep, involving strategy game or a fast paced action game might do.
Also, the fact that they don't fill the screen will automatically reduce my level of immersion, since the illusion that I am actually in the province of Tamriel ( to take Oblivion as an example ) is impossible to maintain when it's side by side on the desktop with Skype, a couple of messageboards and an IDE ( Blide runs almost 24/7 on this PC ;) )
So I'm sure I would mark down any game which was the sort of game which should try to immerse me, or take all of my attention because it's going to fail to do that. If it were ( for example ) a Scrabble game or a sports management game where I was going to flick back and forth with something else by necessity because there are quiet moments in the game where sitting there staring at the screen is largely pointless, then I would probably mark it down if it were NOT running in a window, because it's more helpful to be in a window.
In short, it would depend on the game, and it would work both ways. For me.