Nikon D40 crop a lot/do I need more Megs?

Using Nikon D40 - great camera but use 85mm, f2 prime lens and crop a lot. PROBLEM is when print using standard 4x6, 5x7 or 8x10 size, lot of image cut off b/c pixel count of cropped area too low. Do I need to buy another Nikon w/ higher megs? Looked at Nikon D300, but that model is about twice as HEAVY as the D40 and not thrilled about lugging around all the extra weight. Also, if upgrade would like camera w/ body focus motor to enable using 85mm f/1.8 AF-D, that excludes the D60 which also will not accept the AF-D. ALSO, considered the Nikon 5000, but that's also twice as heavy as the D40 and it was recalled several months ago for manufacturing defects. Any suggestions would be really appreciated. Txs, Rob

ADDENDUM: The PROBLEM should also note the cropped area has too much noise b/c of low-meg in cropped section of photo.

The first possible answer is to crop less - get in closer and really concentrate on getting as much of the frame as possible used. Maybe for your photographic style you could be using a longer lens or a zoom instead? Something like a 50-300mm would solve your problem, but wouldn't be as fast as f2 of course. Do you need the speed?

If you only have one lens I'd really consider an alternative more compact marque and reinvest in new kit altogether. If you're locked into Nikon, which is a good choice by the way, then maybe zooms would be helpful.

Alternatives would be Pentax (K-x with 18-55mm and 55-300mm kit as a package)and Olympus (very compact) but probably not Canon as that will have the same disadvantages as the ones you have already identified.

Hope that helps!

John