it doesn't really matter. in fact it's better to try sizing with both aa on and off, for when viewers have smoothtype turned on (i don't even know how to turn it off in mac osx). some things will look readable with clear type, but with aa, it becomes much harder.
as for the layout, it's tacky in style. the font faces (mostly the script type) and the filters on them are very ameture. it really reminds me of the garbage word art i saw people using in highschool. the script type face is a very 'young', playful font. it's really optimal for things that aren't meant to be taken with a serious attitude, like kids illustration books and the like. here you've used them in a semi serious business driven environment and the attitudes clash. as for the giant strokes/shadows on the titles, imo they take them from bold, powerful titles and cheapen them into more cartoony stuff like the fat script font.
i also don't like your menu. the idea i neat, but it doesn't look like the concept is developed enough. try developing them further then just rectangles. design them to look like those thin bookmark stickies you use for giant textbooks. it gives you more of a "reason" to make the menu like that. i can't tell if it's filters on the font, or the rectangle, but either way, get rid of them. a subtle shadow on the tab to give the layout some depth is cool, but leave the text plan for sure, and keep the typeface moderately professional. don't stick to the same Arial/Verdana type stuff, but keep that kind of credible image in mind. a lot of bad designs are bad, because the designer tried too hard to make it good. good design just happens if you've got it.
the header is something that is starting to bother me. i have no idea what the image is. the left looks like it's on fire, and the right looks like some kind of ice cave/stalagmite. a web site is digital branding. you're calling yourself dashboard designs - this is where you present the reasoning in a visual form. there's absolutely no connection between dashboard and fire. it also looks like there's a glow on it - that or it's bad cropping around the menu and the shadow isn't filling out properly. the url in the header is borderline redundant. if they're at your web site, they can get the url from the address bar if they got there by an external "click here" kind of link. otherwise, they should already know it. right now it feels like random placement and doesn't serve much of a purpose.
generally serif fonts are easier to read because the serifs guide the reader's eye, but they become really ugly when they're not smoothed out. for screen, it's better to use sans-serif fonts because there's less to "break" when you have no aa.
for type faces, you should pick one for the logo / rendered type that still has a seriousness to it (the script and the filters right now are way too playful) and for the content, use something like arial/verdana. and stick to just those tpe faces and use varying weights/sizes/colours to accent them.
also, if you put a shadow on the body, make sure it everywhere. shadows don't just show on the right/left of things.