Latitude D630

I don't know how laptop prices in Canada compare to the US (it's almost never just a straight currency conversion), but that budget won't get you very far if you want a business-grade system like your D630, especially if you want an SSD upgrade since that will be $75-125 all on its own, depending on the capacity you require, and you'll definitely be buying an upgrade there since no system in that price bracket will come with one as standard.  That leaves maybe ~$500 for the system itself, which again isn't a lot for a business-grade system like your D630.  There are $500 systems out there, but they'll feel noticeably cheaper in use.  So if your D630 is otherwise still in good working order, I think you'll get more bang for your buck by buying an SSD and memory upgrade for that system and calling it a day, then waiting until you can spend more on a new system so you get more of an upgrade.  For an SSD upgrade, I recommend the Samsung 860 Evo.  Make sure you get the "traditional" 2.5" laptop drive version, not the mSATA or M.2 card versions.

If you decide you want to replace your entire system, there aren't many 13-inch Latitude systems; most of them are 12, 14, or 15" models, I think because 14" is simply the most popular size for general purpose business use.  You could consider a 12" model, but you might find that a bit difficult to use when you're away from your external displays, and it might actually cost more, since sometimes you pay for thinner and lighter.  The 14" Latitude range would be the E[5/6/7]4xx models, e.g. E6420 or E7440.  The Latitude 6000 range was phased out in favor of the 5000 and 7000 models, but for that price you might only have 6000 range models as an option.

You are the best. I totally agree. I am a graphic designer and do web design as well. What is a good new laptop for around $600 CA?  I am planning ot wait until the holidays for a good price. 

I am looking at 8G, I have external monitors so really even a 13" laptop will do. Thanks.

The main benefit of a 64-bit OS is that it can use more than 4GB of system memory, so if you only have 4GB of memory, you're unlikely to see any real benefit.  You'd also have to perform a clean install of Windows since there's no in-place upgrade path from 32-bit to 64-bit, and even if you manually download and use the "Windows 7 convenience update rollup" package to cut down on the time that would take, you'll still be in for several hours of downloading and installing updates to bring a Windows 7 system current.  A 64-bit OS also allows individual processes to consume more than 2GB of memory, but again if you only have 4GB total, that probably wouldn't happen on your system even if it were allowed.

In terms of upgrades, an SSD would almost certainly be a better way to spend your cash unless Task Manager actually shows you using 75% or more memory.  The reason I mention 75% is that Windows will reduce its memory consumption a bit depending on what's available and always try to keep some memory free, so you don't have to be at 99% for more memory to become useful.  Windows will make use of more memory for caching and such when more is available -- but if on the other hand you're only using 2GB or so, then more is unlikely to make a difference.  An SSD on the other hand would be transformative.

In terms of replacing the system, the D630 is quite old at this point, and you can find decent deals on used but significantly used hardware through retailers like Discount Electronics (if you're in the US), which primarily gets systems that come off corporate lease.  That means they've generally been treated well and are business-grade hardware, so they're built better in the first place.  And they allow you to choose to have an SSD installed even if the system didn't originally come with one, which is an option I'd strongly recommend.  If you've never used an SSD-equipped system, it makes the system easily 3x faster for everyday tasks.  A 5-year-old system with an SSD will feel much faster for those tasks than a brand new system that has a spinning hard drive.

Thank you for your guidance. Something to think about. 

If the notebook serves its purpose of portability, consider simply using it as a terminal for a desktop computer when you need it.  $600 CAD won't get you what you need in a notebook, but the rule of two generally applies -- for power equivalent to a $600 desktop you'll spend at least $1200 on a notebook.  So - buy the desktop for the work the Dx30 won't do easily, and use the laptop for portability (and accessing the desktop when you need it).