Optimisation of IEEE 802.11e MAC protocol performance can be performed by modifying several parameters left open in the standard, like buffer size and acknowledgement policies. In this work, an event driven simulator was developed, and a comparison of the results between the case of standalone services and several services supported simultaneously was addressed. With only a single service, higher values for the goodput are obtained for video and background (BK) traffics, while the lowest is found for the voice application. The number of supported users is higher for voice. With mixtures of traffic, when the number of station is small the goodput is lower for voice. However, for higher number of station, the lowest values of the goodput occur for background traffic. By using the Block Acknowledgement (ACK) procedure, for video and BK traffics, the capacity is improved when the number of station is equal or higher than 16 and 12, respectively. From a detailed analysis of the video application, a reduction of more than 40% was achieved in the delay.