You're question isn't super clear on what your needs are when it comes to speed of the ports. Are you running 100mbit or 1Gbit to each desktop? Either way I would stick with HP for the following reasons.
- HP makes a great product.
- Life time warranty (with no support contracts), I don't know of any other vendor that has this currently.
- Keeping the network equipment single vendor makes managing the network much easier.
I've also had good luck with the Dell PowerConnect switches in cases where budget didn't allow for HP.
But I tend to avoid NetGear after a few bad experiences. I can't speak on the other brands you mention since I haven't had any first hand experience.
I can't speak to American pricing, but if there is a HP ProCurve Switch in your price range then you might want to take a look. I've found their products to be keenly priced (in the UK anyway), great performers, and very well supported products with a very good guarantee.
I'm not personally a fan of DLink in general but can't comment on the specific model you are looking at. Regardless of what model you buy in the end you have the right idea with going from a group of 'home' products to a business class switch, but also consider the environment - clean power, well ventilated, decent cabling will all help...
Your proposed setup looks fine to me, I think you'll certainly see an improvement in reliability and throughput by reducing the quantity of switches and improving their quality. Simple is nearly always better.
You do have to consider that any product, no matter how well built, how well recommended, how well cared for can fail occasionally. If an outage is unacceptable, then whatever product you buy then it might be worth trying to find the money for two in case of a problem. Whether or not the risk vs. investment makes sense for you is something only you can decide.
I can say that from running a major business network, just about every make of 'business class' switch I've used has been very reliable - as long as they're not dead on arrival they should last for a very long time. The ProCurve switches have had the best record in this area for me, which is why I like to suggest them to others.
Best Answer
There's nothing inherently special about an uplink port. You can use those ports to connect to switches or to individual servers (or NAS appliances). The ports can be configured to support VLAN tagging - or, in your case, can be untagged ports in the same VLAN as the 48 GE ports.
Ports 51 and 52 are configurable as either stack ports or uplink (read: normal) ports. The stacking mode is just a proprietary mechanism to make up to 6 of these switches show up as a single device. If you buy more of these switches this might be a handy way of growing your network. If you don't, they're just ports.