Ken,
You can remotely control the CG5 using the freeware Nexstar via a (4 wire) cable from the handcontroller to the serial in port of a PC / laptop - no length restrictions. I made my own cable DB9 connector one end LAN connector into a LAN / Serial interface plug - materials cost 10 dollars or less. I needed a $10 multimetre and $45 crimping tool to make all my special cabling connections.
http://www.nexstarsite.com/NSOL.htm
So Goto from a remote PC with the CG5 is pretty simple once you have the cable and free software. How to wire the cable here
http://www.nexstarsite.com/PCControl/RS232Cable.htm
Ideally its great if you can setup the scope - and not touch it to avoid vibration for astrophotography. So one other think you might later look at is motorised and/or computer controlled focusing, I am a few weeks away from doing remote PC controller focusing - so skip that one for the moment.
e.g.
http://www.store.shoestringastronomy...roducts_fc.htm into a Meade motor focus unit
For auto-guiding you need something to mimic a S-BIG autoguide controller - unless you are fortunate to have an S-BIG unit. However these can be emulated by a PC running the right software as it processes the video in from a ccd. I happen to have bought an Meade DSI which comes with some great planetarium, imaging, focusing, dome control and auto-guding software - for Meade specific electronics. However there are great emulators out there to convert Meade proprietary commands to Celestron commands for alot of your mount control. e.g. Guidestar
http://www.skyinsight.net/wiki/index...tware_Emulator
If I where in your shoes I would research what software you need to control your mount and achieve astrophotography to make a better decision. There is a whole slew of learning and products to process an image once its been captured.
70% of the human brain is devoted to real time visual processing, and its evloved for hundreds of thousands of years. So don't think a simple CCD and some software available to day will do this all for you out of the box. CCDs capture alot of signal, but they don't necessarily present the signal you need to highlight well. They can flood you with the most obivious light data and you may have to tease out the critically important subtle stuff with specific software.
Don't let this put you off, simply continue to ask good questions and read alot is my advice.
If I had to surammise your two stated choices the CG5 is capable but you need to support it with the right software and cabling. The LXD75 is likely to be mechanically inferior but Meade bundle great, integrated software at least with their CCDs to drive their mounts far more benefically then Celestron do.
Celestron - better hardware on the Mount, possible to acquire 3rd party software to do all a Meade s/w package can can. Meade - lesser mount, better, more integrated software in my very limited experience.
What have others found?