Can Anti-virus affect device performance? I have installed some anti-viruses on my device, and since then I am feeling that the performance of the device is quite slow, and when I uninstall them the device works fine, and the device starts heating so quickely. So is this because of Apps from the Market or this issue is with my device.
All antivirus applications on all platforms will impact the performance of the device.
This is because they intercept your actions and check them for unwanted effects.

You say you have installed anti-viruses - plural.  If you install more than one such application on any device they will start to check upon each other.  This will have a significant cumulative affect which will be immediately noticeable.
If you have installed more than one, then uninstall in the reverse order of installation.