  We present XMM-Newton X-ray observations of the interacting galaxy pairs
NGC7771/7770 and NGC2342/2341. In NGC7771, for the first time we are able to
resolve the X-ray emission into a bright central source (L(X)~10^41 erg/s),
plus two (L(X)>10^40 erg/s) ultraluminous X-ray sources (ULXs) located either
end of the bar. The soft emission of the central source is well-modelled by a
two-temperature thermal plasma with kT=0.4/0.7 keV. The hard emission is
modelled with a flat absorbed power-law (Gamma~1.7, NH~10^22 cm^2), and this
together with a low-significance (1.7 sigma) ~300 eV equivalent width emission
line at ~6 keV are the first indications that NGC7771 may host a low-luminosity
AGN. For the bar ULXs, a power-law fit to X-1 is improved at the 2.5 sigma
level with the addition of a thermal plasma component (kT~0.3 keV), while X-2
is improved only at the 1.3 sigma level with the addition of a disc blackbody
component with T(in)~0.2 keV. Both sources are variable on short time-scales
implying that their emission is dominated by single accreting X-ray binaries
(XRBs). The three remaining galaxies, NGC7770, NGC2342 and NGC2341, have
observed X-ray luminosities of 0.2, 1.8 & 0.9x10^41 erg/s respectively (0.3-10
keV). Their integrated spectra are also well-modelled by multi-temperature
thermal plasma components with kT=0.2-0.7 keV, plus power-law continua with
slopes of Gamma=1.8-2.3 that are likely to represent the integrated emission of
populations of XRBs as observed in other nearby merger systems. A comparison
with other isolated, interacting and merging systems shows that all four
galaxies follow the established correlations for starburst galaxies between
X-ray, far-infrared and radio luminosities, demonstrating that their X-ray
outputs are dominated by their starburst components.
