1. Yes. There is a ConvertPdfService in the Foundation component in the API. It takes a PDF document as an input, you provide a set of conversion options and you get a map/list of images back out.
2. Yes. If I understand what you are asking. Through DDX you can query a PDF for DocInfo. Part of that information contains page width and height in pixels. Go look up the DDX reference.
Here is a sample DDX document
<DDX xmlns="http://ns.adobe.com/DDX/1.0/">
<PDF result="result.pdf">
<PDF source="inDoc1" />
</PDF>
<DocumentInformation source="result.pdf" result="doc_info.xml" />
</DDX>
Here is a sample of the data returned in the doc_info.xml.
<DocInfo xmlns="http://ns.adobe.com/DDX/DocInfo/1.0/">
<Title>This is a test doc</Title>
<Author>joe@public.com</Author>
<CreatedDate>2006-12-29T07:22:04Z</CreatedDate>
<ModifiedDate>2009-05-15T13:35:15Z</ModifiedDate>
<Creator>PScript5.dll Version 5.2.2</Creator>
<Producer>Jaws PDF Creator v2.10.987</Producer>
<Version>1.6</Version>
<NumPages>16</NumPages>
<FormType>NotAForm</FormType>
<PageSizes>
<PageSize height="842.0pt" pages="1-16" width="595.0pt"/>
</PageSizes>
<PageRotations>
<PageRotation pages="1-16" rotate90="0"/>
</PageRotations>
<PageLabels>
<PageLabel format="Decimal" pages="1-16" start="1"/>
</PageLabels>
</DocInfo>