You can recycle plastic bottles, pots, tubs and food trays, including plastic tops and lids. A full list plastic containers you can recycle is listed at What Can I Recycle?
It is not particularly helpful to look at the plastic types, as in Westminster you can recycle all of types 1 & 2 but only some of types 5 & 6.
If an item cannot be recycled try to reduce the amount of this type of plastic you produce through your purchasing. Ask your supplier for recyclable alternatives. Non-recyclable plastic must be thrown in the red general waste bags / bin.