General Networking/Lan/Wan/strange network issue
Can you help me to fix issue in my home network as shown on diagram?
First thanks for all the details and the diagram - that is most helpful. A number of things could be contributing but the one thing that really stands out to me is the dlink router and the issues are mostly tied to the wireless network. Bottom line is the router is aging and doing a really bad job of balancing anything out. I expect that it's processor is getting overloaded and it's dropping/queuing packets. This is highlighted by the fact that even the 192.168.0.105 wireless client experiences issues. That router is aging, only supports b/g not N and ... it is "D-LINK". I have tried dlink stuff several times in the past and have always been disappointed, and so will never do so again.
New b/g/n routers are inexpensive and ;pretty powerful. I'd really replace that dlink with something like an asus, linksys, netgear, tp-link, etc. N wireless has MUCH greater range and speed than b/g. So once you put that in, you can get rid of the extra access point and that old switch (which is likely to also be contributing to the problems via packet loss). Keep the network as simple as possible! A second access point shouldn't be necessary at all.
You are clearly pretty technical so you may wish to seriously consider buying a router that already has 3rd party firmware installed on it - or a model that is supported by such 3rd party firmware (DD-WRT and Tomato are very well known versions). http://www.dd-wrt.com/site/index
. With stuff like this, you can leverage advanced QoS policies - to help insure that real-time / interactive flows aren't being impacted by aggressive bursty traffic. And you can even increase the antennae power if you need to (do this only in small amounts and only if you need to - or you can risk burning something out - dd-wrt's site has lots of great advice and forums).